The idea that new policies change the economic rules and affect economic behavior, so that no one can safely assume that historical relationships between variables will hold when policies change, is known as

The rutabaga market is perfectly competitive. Research is published claiming that eating rutabagas leads to gaining weight and so the demand for rutabagas permanently decreases. The permanent decrease in demand results in a

A) lower price, economic losses by rutabaga farmers, and entry into the market. B) lower price, economic losses by rutabaga farmers, and exit from the market. C) higher price, economic profits for rutabaga farmers, and entry into the market. D) higher price, economic losses by rutabaga farmers, and exit from the market. E) lower price, economic profits for rutabaga farmers, and entry into the market.

The Roomba 570 is a robotic vacuum cleaner made and sold by iRobot. It can vacuum 4 rooms on a single battery charge and it costs $10 worth of electricity to charge the Roomba

Lynn is a house cleaner and can vacuum 4 rooms in 1/2 hour with a traditional vacuum. Suppose you want the 4 rooms in your house vacuumed once a week for one year. Ignoring the cost of any electricity Lynn uses, which method is economically efficient if Lynn charges $20 per hour? $30 per hour? A) Lynn if she charges $20 or $30 per hour B) Lynn if she charges $20 per hour and Roomba if Lynn charges $30 per hour C) Roomba if Lynn charges $20 per hour and Lynn if she charges $30 per hour D) Roomba if Lynn charges $20 or $30 per hour