In the long run, under conditions of perfect competition, market forces come into play to

Recessions occur at ________ intervals and are ________ to predict with much accuracy.

a) regular; quite possible b) regular; almost impossible c) irregular; almost impossible d) irregular; quite possible

The figure above shows a tax imposed on a good with an external cost. The area of the rectangle abcd equals

A) the MSB. B) the total tax revenue collected by the government. C) the amount of pollution tax per ton. D) the MC. E) the deadweight loss.