If ten cases of pretzels are sold at a price of $8 each and the marginal product of the last unit of labor is 5, the firm's total revenue is

One reason why, in the last four decades, the number of new auto makers in the world has been very small compared to the past is that

A) the automobile cannot be improved upon in any way by new producers. B) new auto makers cannot obtain necessary inputs to produce new cars. C) governments restrict who can produce automobiles. D) new producers cannot match the economies of scale of existing auto makers.

Suppose the MPC in an economy is 0.9. The APC is initially 0.95 and disposable income is $4 billion. If disposable income increases to $14 billion, what is the new level of consumption?

A. $12.8 billion. B. $12.6 billion. C. $13.3 billion. D. $9 billion.