The Solo Coal Mine is the only employer in the small town of Way out there. The market supply of coal miners is Qs = 0.02W - 200, where W is the annual wage of a coal miner and Q is the number of people who would accept employment as a coal miner. What is the coal mine's marginal expenditure function?

If the U.S. government enters the foreign exchange market and sells dollars to maintain a specific exchange rate with the yen, the dollar will ________ and the yen will ________

A) depreciate; depreciate B) depreciate; appreciate C) appreciate; depreciate D) appreciate; appreciate

Suppose the production of mp3 players can be represented by the following production function: q = L0.4K0.4. Which of the following statements is TRUE?

A) The production function has decreasing returns to scale. B) The production function has increasing returns to scale. C) The production function has constant returns to scale. D) Returns to scale vary with the level of output.