Cost curves in the long run differ from cost curves in the short run

The marginal product of capital (MPK) is given by the ________

A) capital share of income + average output per unit of capital B) capital share of income - average output per unit of capital C) capital share of income ÷ average output per unit of capital D) capital share of income × average output per unit of capital E) none of the above

One explanation for the drop in the standard of living in the Soviet Union during World War II is that

a. the war led to a movement along its production possibilities frontier away from civilian goods and towards military goods b. the war led to an outward shift in the production possibilities frontier due to a rise in the level of technology c. prior to the war, there was much productive inefficiency in the Soviet Union d. the opportunity cost of producing military goods was zero in their economic system e. resources used to produce civilian goods were equally capable of producing military goods