People's skepticism about central bankers' announcements of their intentions stems from the fact that policymakers may act in a fashion that is time inconsistent

One reason for the rise in the natural rate of unemployment from 1960 to 1980 is

A) changes in the demographic composition of the work force. B) the decline in inflation. C) increased competition from foreign workers. D) the depreciation of the dollar relative to foreign currencies.

Exhibit 30-3 Costs of Eliminating:Firm A Firm B Firm C 1st ton of pollution$ 30 $ 50 $  600 2nd ton of pollution$ 70 $ 90 $  700 3rd ton of pollution$125 $150 $  900 4th ton of pollution$200 $250 $1,300 Refer to Exhibit 30-3. What is the cost to Firm C of eliminating 2 tons of pollution?

A. $1,300 B. $300 C. $1,500 D. $2,200 E. $3,500