If a firm produces 8 units of output with average fixed cost=$40 and average variable cost=$25, what is its total variable cost?

The additional revenue a firm obtains when it hires an additional worker (holding other inputs constant) is the

A) marginal revenue product (MRP) of labor. B) total factor cost (TFC) per worker. C) general rule for hiring. D) marginal physical product (MPP) of labor.

The price of a ride on the Washington, D.C. metro depends on the time of day you ride. This is an example of

A. exploitation. B. inefficiency. C. political interference with a market. D. pricing to spread out demand.