21) Jenny spends her income entirely on good X (an inferior good) and Good Y (a normal good). What happens to Jenny's consumption of goods X and Y if her income doubles?

Her purchase of good X goes up and purchase of good Y goes up.

Her purchase of good X goes up and purchase of good Y goes down.

Her purchase of good X goes down and purchase of good Y goes down.

Her purchase of good X goes down and purchase of good Y goes up.

24) If income falls, then the equilibrium consumption of that good

increases if it is an inferior good.

increases if it is a normal good.

remains the same.

could increase or decrease if it is a normal good

26) Suppose the growth rate of the firm's profit is 7 percent, the interest rate is 9 percent, and the current profits of the firm are $60 million. What is the value of the firm?

$289.4 million

$3,270 million

$4,480.6 million

$375 million

27) At what level of output does marginal cost equal marginal benefit?

Number Units Produced	Total Benefit	Total Costs
0	0	0
10	120	40
20	200	100
30	270	170
40	310	260
50	330	370

10

20

30

40