Suppose there is a market in which the firms hold the following market shares: 25%, 20%, 18%, 15%, 8%, 7%, 4%, 2%, 1%. What is the concentration ratio for this market?

The Sherman Act of 1890 was passed to prohibit

A) combinations, trusts, or conspiracies to restrict interstate or international trade. B) monopolization or attempts to monopolize interstate or international trade. C) both of the above. D) neither of the above.

Hector's wealth is zero, he expects to work for another 45 years at a constant salary of $80,000 and live for another 60 years. If yearly taxes are $20,000 and Hector completely smooths consumption over his lifetime, his annual consumption is

A) $37,500. B) $45,000. C) $60,000. D) $70,000.