If Tom does not tattle, what would Sarah's best response be

If the marginal private benefit of attending college for Shelly is $40,000 and the marginal external benefit is $15,000, she will attend college if the cost of attendance is no more than

A) $55,000. B) $45,000. C) $40,000. D) $25,000. E) $15,000.

Refer to the table above. What is the total cost incurred per month if Ryan rents Apartment 3?

A) $2,000 B) $2,050 C) $2,150 D) $2,270