CHAPTER 1
ENVIRONMENTAL PROBLEMS,
THEIR CAUSES, AND SUSTAINABILITY
Outline
1-1 What are some principles of sustainability?
A. Environmental science is a study of connections in nature.
2. Environmental science studies how the earth works, our interaction with the earth, and ways to
deal with environment problems and live more sustainably.
4. Environmentalism is a social movement dedicated to protecting life support systems for all
species.
B. Nature’s survival strategies follow three principles of sustainability.
1. Life depends on solar energy.
3. Chemical/nutrient cycling means that there is little waste in nature.
C. Sustainability has certain key components.
2. Many human activities can degrade natural capital.
4. Sustainability begins at personal and local levels.
D. Some resources are renewable and some are not.
2. A perpetual resource is continuously renewed and expected to last (e.g. solar energy).
4. Sustainable yield is the highest rate at which a renewable and non-renewable resource can be used
indefinitely without reducing its available supply.
5. Some resources are not renewable.
A. Nonrenewable resources exist in fixed quantities.
6. Sustainable solutions: Reduce, reuse, and recycle.
E. Rich and poor countries have different environmental impacts.
1. Developed countries include the high income ones, such as the U.S. and Canada.
1-2 How are our ecological footprints affecting the earth?
A. We are living unsustainably.
1. Environmental, or natural capital, degradation is occurring.
2. We have solutions to these problems that can be implemented.
B. Pollution comes from a number of sources.
1. Point sources are single, identifiable sources (e.g., smokestack).
3. We can clean up pollution or prevent it.
5. Pollution prevention reduces or eliminates the production of pollutants.
C. The tragedy of the commons: overexploiting shared renewable resources.
1. In 1968, the biologist Garrett Hardin called the degradation of openly shared resources the tragedy
2. Reducing degradation.
a. Reduce use by government regulations.
b. Shift to private ownership.
D. Ecological footprints: our environmental impacts.
1. Ecological footprint is the amount of biologically productive land and water needed to supply a
3. Ecological deficit means the ecological footprint is larger than the biological capacity to replenish
resources and absorb wastes and pollution.
5. Footprints can also be expressed as number of Earths it would take to support consumption.
6. Case study: A vision of a more sustainable world in 2060.
E. IPAT is another environmental impact model
1. In the early 1970s, scientists Paul Ehrlich and John Holdren developed the IPAT model.
2. I (environmental impact) = P (population size) x A (affluence/person) x T (technology’s beneficial
1-3 Why do we have environmental problems?
A. Experts have identified four basic causes of environmental problems:
2. Unsustainable resource use.
4. Excluding environmental costs from market prices.
B. The human population is growing exponentially at a rapid rate.
2. Human population in 2009 was about 6.8 billion.
4. We can slow population growth; see Core Case Study.
C. Affluence has harmful and beneficial environmental effects.
2. Average American consumes 30 times as much as the average consumer in India.
4. Affluence has provided better education, scientific research, and technological solutions, which
result in improvements in environmental quality (e.g., safe drinking water).
D. Poverty has harmful environmental and health effects.
1. Poverty occurs when the basic needs for adequate food, water, shelter, health, and education are
not met.
3. Poverty causes harmful environmental and health effects.
a. Environmental degradation caused by need for short-term survival.
b. Malnutrition.
c. Inadequate sanitation and lack of clean drinking water.
d. Severe respiratory disease (inadequate ventilation of heat sources).
e. High rates of premature death for children under the age of 5 years.
E. Prices of goods and services due not include harmful environmental and health costs.
1. A company’s goal is often to maximize the profit.
3. Government subsidies may increase environmental degradation.
4. There are ways to include harmful costs of goods and services.
a. Shift from environmentally harmful to beneficial government subsidies.
b. Tax pollution and waste heavily while reducing taxes on income and wealth.
F. People have different views about environmental problems and their solutions.
2. Environmental ethics are beliefs about what is right and wrong with how we treat the
environment.
4. Stewardship worldview holds that we can and should manage the earth for our benefit, but that we
have an ethical responsibility to be caring and responsible managers.
1-4 What is an environmentally sustainable society?
A. Environmentally sustainable societies protect natural capital and live off its income.
1. Increase reliance on renewable resources.
2. Protect earth’s natural capital.
B. We can work together to solve environmental problems.
1. Trade-off solutions provide a balance between the benefits and the costs.
1-1 What are some principles of sustainability?
CONCEPT 1-1A Life on the earth has been sustained for billions of years by solar energy,
biodiversity, and chemical cycling.
CONCEPT 1-1B Our lives and economies depend on energy from the sun and on natural resources
and ecosystem services (natural capital) provided by the earth.
1. Define natural capital. Make a list of several local examples of depleting or degrading
2. Describe how natural services work to recycle materials. Draw the relationship between
3. Distinguish between the following terms: inexhaustible, renewable, and nonrenewable
resources and specify the importance of reduce, reuse, and recycle for the nonrenewable
resources.
CONCEPT 1.1C We could shift toward living more sustainably by applying full-cost pricing,
searching for win-win solutions, and committing to preserving the earth’s life-support system for
future generations.
1-2 How are our ecological footprints affecting the earth?
CONCEPT 1-2 As our ecological footprints grow, we are depleting and degrading more of the
earth’s natural capital.
1. Distinguish between point and nonpoint sources of pollution. Describe two local examples of each
type and suggest recommend solutions to reduce or eliminate these problems.
3. Give 3 examples of resources that have been degrade due to the tragedy of the commons.
1-3 Why do we have environmental problems?
CONCEPT 1-3A Major causes of environmental problems are population growth, unsustainable resource use,
poverty, avoidance of full-cost pricing, and not including the harmful environmental costs of resource use in the
market prices of goods and services.
CONCEPT 1-3B Our environmental worldviews play a key role in determining whether we live unsustainably
or more sustainably.
1. What is affluenza? List several behaviors that you have observed that are signs of affluenza. What are
the long-term consequences of continued high levels of consumption?
2. Describe several environmental problems associated with poverty. Distinguish between developed
countries and developing countries.
1-4 What is an environmentally sustainable society?
CONCEPT 1-4 Living sustainably means living off the earth’s natural income without depleting or degrading
the natural capital that supplies it.
2. Define biodiversity. Briefly describe your community’s biodiversity. Analyze the relationship
between biodiversity and human life.
Key Terms
biodiversity
chemical cycling
environmental
worldview
environmentalism
environmentally sustainable
society
exponential growth
exhaustible resource
full-cost pricing
human-centered worldview
inexhaustable resource
resource
nutrient cycling
nutrients
organism
per capita ecological
footprint
point sources
pollution pollution cleanup
pollution prevention
poverty
sustainable yield
Teaching Tips
Ask students to look up their hometown’s 1990 and 2000 census population at www.census.gov; or let the
students know that around 1900 the world population was approximately 2 billion and around 1975
approximately 4 billion, then ask them what our current population is. Ask them how these numbers have
influenced their quality of life. Use this dramatic change in population to introduce the core case study.
• Using the notion of exponential population growth, move on to ask them how long this unchecked
population growth can go on.
• Discuss how different cultures distribute resources, then ask the students (1) how their parents
distributed the family resources, such as groceries, tuition money and entertainment expenses and
(2) how the students handle their own resources.
• Stress the idea of a sustainable society, how this type of society can grow, and humans’ effect on
Chapter 1: Environmental Problems, Their Causes, and Sustainability
Discussion Topics
1. What are the UN population projections and how might these population changes influence
sustainability?
2. Define poverty and specify several geographic areas struggling with poverty. Discuss several causes of
poverty. Suggest possible strategies to address the current situation.
4. State of the world: Use the annotated bibliography of current resources to summarize the state of the
world and the most important areas of environmental concern.
6. How have cultural views of the human-environment relationship influenced a sustainable-Earth
worldview? What about indigenous cultures? Discuss attitudes toward nature; distribution of labor,
7. How has energy consumption and use of materials throughout history changed in relation to increases
in population size?
8. What variables influence a person’s quality of life? What are the minimum requirements for each
person to have a “good” quality of life? What is a “good life”? Does increased resource consumption
improve quality of life?
9. What is the history of conflict among pollution control, environmental degradation, and employment in
the United States? List possible cases of interest such as the automobile industry and fuel efficiency
10. Is the United States overpopulated? What is the difference between people overpopulation and
consumption overpopulation?
11. Do you feel a part of or apart from nature?
12. Do you think technology can solve our environmental problems?
13. Do you think human ingenuity, technology and substitutes for materials that are being used up quickly
can create a good life for Earth’s people?
14. When poor economic growth accompanies population growth, poverty increases. How does the use or
misuse of natural/renewable resources affect poverty? How does this poverty affect the environment?
How can the use of common property affect resources?
Instructor’s Manual for Environmental Science, 15th edition
Activities and Projects
1. Create an environmental movie list: each student submits a movie title, description, and how it is
2. Compare your family size and resource consumption to that of your parents or grandparents. Make a
3. As a class project, “adopt” a country. Assign teams of students to investigate various aspects of the
4. Find and share with the class songs, essays, poems, paintings, and literary passages that are strongly
pro- or anti-technology/environment.
5. As a class exercise, make lists of the beneficial and harmful consequences that have resulted from
America’s adoption of automobile technology. Survey the class to see how often students travel by
6. As a class project or extra-credit exercise, contact the local Department of Transportation (DOT) and
find out if they offer an Adopt-A-Highway program. Adopt a stretch of highway and have the students
7. Find and share with the class songs, folklore, literary passages, and artwork that reflect U.S. land-use
values and ethics as they have evolved from the frontier era to the present. Be sure to include Native
American works. What can be discerned about the relationship of humans to nature in different
cultures through their expressions of art?
9. Have your students survey four of their friends or family members to determine their worldview. Pool
Attitudes and Value Assessment
1. Are we living on our planet in a sustainable manner?
2. Is the world overpopulated? Have you experienced countries that you felt to be overpopulated? Have
you seen videos of countries that you felt to be overpopulated?
3. Is your local community overpopulated? What do you feel are the costs and benefits of the population
size of your community?
© 2016 Cengage Learning
6. Do you think the rate of resource consumption is too high?
7. Do you consume too many resources? Should your ecological footprint be regulated?
8. Do you think it’s important to change your consumption patterns?
9. What kinds of changes do you think would improve the quality of life on Earth?
10. What kinds of changes are you willing to make to decrease your resource consumption?
Laboratory Skills
Wells, Edward. Lab Manual for Environmental Science. 2009. Lab #2: The Tragedy of the Commons—A
Classroom Simulation Exercise.
News Videos
Sacrificing the environment for energy?; Brooks/Cole Environmental Science Video Library 2010 with
Workbook, ©2012, DVD ISBN-13: 978-0-538-73495-0
Additional Videos
Planet Earth: The Future: Living Together (Documentary, 2007). Companion to the BBC nature
documentary Planet Earth. Three episodes: “Saving Species,” “Into the Wilderness,” and “Living
Together.”
Reinventing the World (Documentary, 2000). Explores some of the biggest challenges facing us today,
including urban sustainability.
Web Resources
Center for Sustainable Economy
Earth 911.org
Environmental and sustainability resources.
http://earth911.org/
Online Community for the Environment
Digital Integration
Correlation to Global Environment Watch
Consumption Overpopulation
Ecological Footprint Poverty
Environmental Philosophy Sustainability
Correlation to Explore More
Sustainability
Suggested Answers to End of Chapter Questions
Answers will vary, but these represent phrases from this chapter. The following are examples of the
material that should be contained in possible student answers to the end of chapter questions. They
Review
Core Case Study
1. Define sustainability, and summarize the story of how many college campuses are working to become
more environmentally sustainable.
• Sustainability is the capacity of the earth’s natural systems and human cultural systems to survive,
Chapter 1: Environmental Problems, Their Causes, and Sustainability
•
Section 1-1
2. What are the three key concepts for this section? Define environment. Distinguish among environmental
science, ecology, and environmentalism. Distinguish between an organism and a species. What is an
ecosystem? What are three scientific principles of sustainability derived from how the natural world works?
What is solar energy and why is it important to life on the earth? What is biodiversity and why is it
important to life on the earth? Define nutrients. Define chemical cycling (or nutrient cycling) and explain
why it is important to life on the earth.
The key concepts for this section are:
o Nature has sustained itself for billions of years by relying on solar energy, biodiversity,
and nutrient cycling.
o Our lives and economies depend on energy from the sun (solar capital) and natural
resources and natural services (natural capital) provided by the earth.
• The environment is everything around us.
• Environmental science is an interdisciplinary study of how humans interact with living and
nonliving parts of their environment.
• Ecology is the biological science that studies how organisms, or living things, interact with one
another and with their environment.
• Environmentalism is a social movement dedicated to protecting the earth’s life-support systems
3. Define natural capital. Define natural resources and ecosystem services, and give two examples of
each. Give three examples of how we are degrading natural capital. Explain how finding solutions to
environmental problems involves making trade-offs. Explain why individuals matter in dealing with
the environmental problems we face. What are three social science principles of sustainability? What is
full-cost pricing and why is it important?
4. What is a resource? Distinguish between a resource and a renewable resource and give an example of
each. What is the sustainable yield of a renewable resource? Define and give two examples of a
nonrenewable resource. Distinguish between recycling and reuse and give an example of each. What
percentage of the non-renewable metals and plastics that we use could be recycled or reused?
Distinguish between more-developed countries and less-developed countries and give an example of a
high-income, middle-income and low-income country.
• A resource is anything obtained from the environment to meet our needs and wants such as solar
energy, fresh air, fertile soil, wild edible plants, petroleum, iron, underground water, and cultivated
crops.
• Solar energy is called a perpetual resource because it is renewed continuously and is expected to
last at least 6 billion years as the sun completes its life cycle.
• A renewable resource can be replenished in days to several hundred years through natural
Section 1-2
5. What is the key concept for this section? Define and give three examples of environmental degradation
(natural capital degradation). About what percentage of the earth’s natural or ecosystem services have
been degraded by human activities? Define pollution. Distinguish between point sources and nonpoint
sources of pollution and give an example of each. Distinguish between pollution cleanup and pollution
prevention. Describe three drawbacks to solutions that rely mostly on pollution cleanup. What is the
tragedy of the commons and what are two ways to deal with it?
• The key concept for this section is:
o As our ecological footprints grow, we are depleting and degrading more of the earth’s
natural capital.
• Environmental degradation is when the use of a renewable resource exceeds its natural
Chapter 1: Environmental Problems, Their Causes, and Sustainability
• Point sources are single, identifiable sources, such as the smokestack of a coal-burning power or
industrial plant, a factory drainpipe, or the exhaust pipe of an automobile. Nonpoint sources are
dispersed and often difficult to identify. Examples include pesticides blown from the land into the
air and the runoff of fertilizers, pesticides, and trash from the land into streams and lakes.
• Pollution cleanup involves cleaning up or diluting pollutants after they have been produced, for
example water filters used to clean contaminated groundwater. Pollution prevention reduces or
eliminates the production of pollutants, for example air purifying technologies used on smoke
stacks for cleaner exhaust.
• Drawbacks to solutions that rely on pollution cleanup include:
o It is only a temporary bandage as long as population and consumption levels grow without
6. What is an ecological footprint? What is a per capita ecological footprint? Use the ecological footprint
concept to explain how we are living unsustainably. What is meant by upcycling? What is the IPAT
model for estimating our environmental impact?
• An ecological footprint is the amount of biologically productive land and water needed to
indefinitely supply the people in a particular country or area with renewable and non-renewable
resources and to absorb and recycle the wastes and pollution produced by such resource use.
• A per capita ecological footprint is the average ecological footprint of an individual in a given
country or area.
Section 1-3
7. What are the two key concepts for this section? Identify five basic causes of the environmental
problems that we face. What is exponential growth? What is the rule of 70? What is the current size of
the human population? About how many people are added each year? How big is the population
projected to be in 2050? How do Americans, Indians, and the average people in the poorest countries
compare in terms of average resource consumption per person? What are two types of environmental
damage resulting from growing affluence? How can affluence help us to solve environmental
problems?
Instructor’s Manual for Environmental Science, 15th edition
• The two key concepts for this section are:
o Major causes of environmental problems are population growth, unsustainable resource
use, poverty, avoidance of full-cost pricing, and increasing isolation from nature. Our
environmental worldview plays a key role in determining whether we live unsustainably
or more sustainably.
• Five basic causes of environmental problems are:
o population growth
• Exponential growth occurs when a quantity such as the human population or pollution increases at
a fixed percentage per unit of time, for example 2% per year. Exponential growth starts off slowly.
But after only a few doublings, it grows to enormous numbers because each doubling is twice the
total of all earlier growth.
• The rule of 70 is that the doubling time of the human population or of any growing quantity can be
calculated by using the rule of 70: doubling time (years) = 70/annual growth rate (%).
8. What is poverty and what are three of its harmful environmental and health effects? About what
percentage of the world’s people struggle to live on the equivalent of $1.25 a day? About what
percentage struggle to live on $2.25 a day? Explain the connection between poverty and population
growth. Describe three major health problems suffered by many of the world’s poor.
• Poverty is a condition in which people are unable to fulfill their basic needs for adequate food,
water, shelter, health care, and education.
• According to the World Bank, about 900 million people—almost three times the U.S.
population—live in extreme poverty, struggling to live on the equivalent of less than $1.25 a day
9. Explain how exclusion of the harmful environmental and health costs of production from the prices of
Chapter 1: Environmental Problems, Their Causes, and Sustainability
goods and services is related to the environmental problems we face. What is the connection between
government subsidies, resource use, and environmental degradation? What are two ways to include the
harmful environmental and health costs of the goods and services in their market prices? Explain how
a lack of knowledge about nature and the importance of natural capital, along with our increasing
• Because the prices of goods and services do not include most of their harmful environmental and
health costs, consumers and decision makers have no effective way to evaluate these harmful
effects.
• Although subsidies help to create jobs, and stimulate economies, environmentally harmful
subsidies encourage the depletion and degradation of natural capital.
• Two ways to include the harmful environmental and health costs of the goods and services in their
market prices over the next two decades would be to shift from environmentally harmful
government subsidies to environmentally beneficial subsidies, and to tax pollution and waste
heavily while reducing taxes on income and wealth.
• Because people live isolated from nature, they are unaware of the amounts of wastes and
pollutants they produce, where these wastes and pollutants go, and how they affect the
environment.
Section 1-4
10. What is the key principle for this section? What is an environmentally sustainable society? What is
natural income and what does it mean to live off of natural income? What are two pieces of good news
about making the transition to a more sustainable society? Based on the three scientific principles of
sustainability, and the three social science principles of sustainability, what are the three important
ways to make a transition to sustainability as summarized in this chapter’s three big ideas? Explain
how we can use these six principles of sustainability to move us toward a more sustainable future.
• Living sustainably means living off the earth’s natural income without depleting or degrading the
Instructor’s Manual for Environmental Science, 15th edition
Critical Thinking
1. Do you think you are living unsustainably? Explain. If so, what are the three most environmentally
unsustainable components of your lifestyle? List two ways in which you could apply each of the three
principles of sustainability and each of the three social science principles of sustainability to making
your lifestyle more environmentally sustainable.
2. What are three ways in which college campuses (Core Case Study) are employing upcycling by
expanding their beneficial environmental impacts? What are three ways in which you could do this in
your daily life?
Student answers will vary depending on their viewpoint.
3. For each of the following actions, state one or more of the three scientific principles of sustainability
that are involved: (a) recycling aluminum cans; (b) using a rake instead of a leaf blower; (c) walking or
bicycling to class instead of driving; (d) taking your own reusable bags to the grocery store to carry
your purchases home; (e) volunteering to help restore a prairie; and (f) lobbying elected officials to
require that 20% of your country’s electricity be produced by renewable wind power by 2030.
The three key factors are solar energy, biodiversity, and chemical cycling. All the examples could be
connected to all three key factors.
Chapter 1: Environmental Problems, Their Causes, and Sustainability
(c) Reliance on Solar Energy/Biodiversity: By not using gasoline to drive the car, you are relying more
on renewable rather than nonrenewable energy and positively impacting biodiversity in areas where oil
drilling is having harmful ecological effects.
4. Explain why you agree or disagree with the following propositions:
a. Stabilizing population is not desirable because, without more consumers, economic growth would
stop.
b. The world will never run out of resources because we can use technology to find substitutes and to
help us reduce resource waste.
c. We can shrink our ecological footprints while creating beneficial environmental impacts.
5. What do you think when you read that the average American consumes 30 times more resources than
the average citizen of India? Are you skeptical, indifferent, sad, helpless, guilty, concerned, or angry
about this fact? Can you think of something that you and others could do to address this problem?
What might that be?
Again student answers will vary, but the benefit of such questions is that the instructor can facilitate a
discussion that could help the students come to terms with the feelings they have on the issue and take
6. When you read that at least 19,000 children age 5 and younger die each day (13 per minute) from
preventable malnutrition and infectious disease, how does it make you feel? Can you think of
something that you and others could do to address this problem? What might that be?
7. Explain why you agree or disagree with each of the following statements: (a) humans are superior to
Instructor’s Manual for Environmental Science, 15th edition
other forms of life; (b) humans are in charge of the earth; (c) the value of other forms of life depends
only on whether they are useful to humans; (d) based on past extinctions and the history of life on the
earth over the last 3.8 billion years, biologists hypothesize that all forms of life eventually become
extinct, and we should not worry about whether our activities cause their premature extinction; (e) all
forms of life have an inherent right to exist; (f) all economic growth is good; (g) nature has an almost
unlimited storehouse of resources for human use; (h) technology can solve our environmental
problems; (i) I do not believe I have any obligation to future generations; and (j) I do not believe I have
any obligation to other forms of life.
Student answers will vary and the instructor has the opportunity to lead a discussion where each
student can elaborate on their own particular viewpoint. Some comments may include:
(b) Humans are in charge of the earth. No other species can manipulate the environment and exploit
nature for food and energy sources to the same extent. .
(c) Some species need to exist because they may be beneficial to other species in their ecosystem. Just
because they may not benefit humans directly, they do so indirectly by helping to maintain the
biodiversity and stability of ecosystems. In addition, some people believe that other species may have
aesthetic, moral and ethical value.
(f) Economic growth is good for everyone. For example, the people of the U.S. and Europe benefit
from being able to buy cheap goods that are manufactured in China; the Chinese people have jobs, so
everyone wins. Some students may believe that economic growth is bad because it can hurt the
environment; building housing developments means cutting down trees and destroying homes of many
animals.
(g) This is true only if we use the resources in a sustainable way. If everyone on the planet used and
consumed resources at the same rate as the people of the United States, we would run out very quickly
and need more than one Earth to provide the resources for all of us. So, the resources we have are not
unlimited.
8. What are the basic beliefs within your environmental worldview? Record your answer. Then, at the
end of this course, return to your answer to see if your environmental worldview has changed. Are the
beliefs included in your environmental worldview consistent with the answers you gave to Question 7
above? Are your actions that affect the environment consistent with your environmental worldview?
Explain.
Student answers will vary. This question provides the instructor with the basis for a discussion on
individual worldviews and allows for each student to consider their own current beliefs. It is hoped that
Global Environment Watch Exercise
Use the world maps in Figure 1, p. S00, in Supplement 4 and Figure 1.10 to choose one more-
developed country and one less-developed country to compare their ecological footprints (found under
Quick Facts on the country portal). Click on the ecological footprint number to view a graph of both
the ecological footprint and biocapacity of each country. Using those graphs, determine whether these
countries are living sustainably or not. What would be some reasons for these trends?
Ecological Footprint Exercise
1. If the ecological footprint per person of a country or the world is larger than its biological capacity per
person to replenish its renewable resources and absorb the resulting waste products and pollution, the
country or the world is said to have an ecological deficit. If the reverse is true, the country or the world
has an ecological credit or reserve. Use the data below to calculate the ecological deficit or credit for
the countries listed. (As an example, this value has been calculated and filled in for World.)
The two countries with the largest ecological deficits are the United States (-5.1 hectares per person)
2. Rank the four countries with ecological credits in order from the highest to the lowest credit. For each
of these countries, why do you think it has an ecological credit??
The four countries that have ecological credits are Russia (2.2 hectares per person), Brazil (6.7 hectares
2. Rank the countries in order from the largest to the smallest per capita ecological footprint.
Countries listed in order of largest to smallest per capita ecological footprint:
Saudi Arabia
4
0.07
-3.93
Israel
4
0.3
-3.7
Japan
4.2
0.6
-3.6
UK
4.7
1.3
-3.4
United States
7.2
3.9
-3.3
Germany
4.6
2
-2.6
Mexico
3.3
1.4
-1.9
South Africa
2.6
1.2
-1.4
China
2.1
0.9
-1.2
Guatemala
1.8
1.1
-0.7
India
0.9
0.5
-0.4
Nigeria
1.4
1.2
-0.2
Russia
4.4
6.6
2.2
Brazil
2.9
9.6
6.7
Australia
6.7
14.6
7.9
Canada
6.4
14.9
8.5