21) If the income elasticity of demand for lard is -3.00, this means that:
A.lard is a substitute for butter.
B.lard is a normal good.
C.lard is an inferior good.
D.more lard will be purchased when its price falls.
22) The lowest point on a purely competitive firm’s short-run supply curve corresponds
to:
A.the minimum point on its ATC curve.
B.the minimum point on its AVC curve.
C.the minimum point on its AFC curve.
D.the minimum point on its MC curve.
23) The slope of a line parallel to the horizontal axis is:
A.zero.
B.one.
C.infinite.
D.one-half.
24) Economists claim that a farmer who owns her land and provides all her own labor,
and calculates her profits from the farm by subtracting explicit costs from total
revenues, will:
A.Overstate her accounting profits
B.Understate her accounting profits
C.Overstate her economic profits
D.Understate her economic profits
25) If an oligopolist’s demand curve has a “kink” in it, then over some interval:
A.The oligopolist’s marginal cost curve will have a break in it
B.The oligopolist need not fear entry into the industry by new firms