Fluency with Information Technology, 6e (Snyder)
Chapter 21 A Case Study in Algorithmic Problem Solving: The Smooth Motion Application
21.1 True/False Questions
1) The Decomposition Principle can only be applied to the main task, not to any subtasks.
2) You must solve independent tasks before tasks which depend on them.
3) The Smooth Motion program uses 140 separate images to fill its 7 x 20 grid.
4) When using images in HTML, it is recommended that they be placed in a separate folder.
5) When the Smooth Motion web page first loads, before the JavaScript starts to run, the initial images
for the grid animation are added to the page the simple way, with 20 <img> tags typed into the
document.
6) In the Smooth Motion application, when the user has not moved the mouse over any key image, the
rightmost image is chosen at random.
7) In the Smooth Motion application, when the mouse enters one of the key images, that event runs
some JavaScript code which assigns the rightmost image of the animation grid.
1) A PERT chart
A) shows which tasks must be completed before which others.
B) displays the layout of elements on an HTML page.
C) gives a symbolic representation of the iterations of a for loop.
D) represents the structure of a JavaScript program.
2) When the Smooth Motion application animates the motion of the columns across the page,
document.images[i] is replaced by
A) document.images[i-1]
B) document.images[2*i]
C) document.images[i+1]
D) document.images[0]
3) In the Smooth Motion program, the images move
A) from right to left.
B) from left to right.
C) from top to bottom.
D) diagonally.
4) A mouseout event means
A) the user clicked on an image (or other object a web page).
B) the mouse has moved onto an image (or other object a web page).
C) the mouse has moved away from an image (or other object a web page).
D) the mouse has moved away from the browser window.
5) The build UI task
A) comes first, so the JavaScript will have something to work with.
B) comes last, once you know what the page will try to do.
C) comes after animate grid, but before the sense keys task (that the user actually interacts with).
D) can be done at any time, since its independent of the other tasks.
6) For the Smooth Motion application, the final JavaScript function animate does two things: it updates
the animation images, and
A) recomputes the amount of time needed before the next call to animate.
B) moves the key images to new locations on the web page.
C) checks if the mouse is moving smoothly or not.
D) computes the exact amount of time since the mouse crossed any key image.
7) Some task solutions rely or depend on the solution to some other task. These are called
A) ordering requirements.
B) task dependencies.
C) work orders.
D) sequencing events.
8) Another name for a PERT chart is a(n)
A) ZIP display.
B) work influence diagram.
C) iteration variable.
D) task dependency graph.
9) In the Smooth Motion app, the third key image is represented in HTML as
<img src=”gifpix/OrangeBox.gif” onmouseover=”here(2)” onmouseout=”gone(2)”>
What is the purpose of the number 2?
A) It specifies the number of key images.
B) It tells the event function which box was crossed by the mouse.
C) It indicates the number of operations which the functions here and gone should perform.
D) It gives the size of the key image.
1) The first step in solving any problem is ________.
2) Dividing a large task into smaller subtasks that can be solved separately is known as the ________.
3) When the mouse moves over an image, a(n) ________ event is recognized.
4) When the mouse moves off the object, a(n) ________ event is recognized.
5) The ________ task is to move the block stacks to the left.
6) The ________ task is to recognize when the user has “met the test.”