An economy has no imports or income taxes. The MPC is 0.75 and real GDP is $120 billion. Businesses increase investment by $4 billion. The multiplier is ________ and the change in real GDP from the increase in investment is ________ billion

An economy's production function is Y = A , and the economy's total output in equilibrium is $700 billion. Total labor income in this economy is ________

A) $300 billion B) $233.3 billion C) $210 billion D) $400 billion E) none of the above

There are currently N identical firms in a market. If it is a perfectly competitive market, the short-run market supply curve at any given price is

A) N times the supply of an individual firm. B) N - 1 times the supply of an individual firm. C) N plus the supply of an individual firm. D) It cannot be determined from the information provided.