Question

In some states, mining for coal leaves large mounds of rubble, which poses flooding problems, causes land damage, and is unsightly. The following table shows the estimated annual social benefits and costs of restoring various amounts of such land:

Land restored (in acres)	0	100	200	300	400	500
Social benefits (per 100 acres)	0	$110	$200	$280	$350	$420
Social costs (per 100 acres)	0	$50	$120	$200	$300	$430

(a) Compute the marginal social benefits and the marginal social costs for each restoration level:

Instructions: Enter your responses as a whole number.

Land restored (in acres)	0	100	200	300	400	500
Marginal social benefit (per 100 acres)	-	$	$	$	$	$
Marginal social cost (per 100 acres)	-	$	$	$	$	$

(b) What is the optimal rate of land restoration?

acres