Household spending on goods and services amounts for what percentage of GDP?

When a monopolistically competitive firm's demand curve shifts leftward, what happens to its marginal revenue curve?

A) Nothing, the marginal revenue curve is unchanged. B) It disappears. C) It shifts rightward. D) It shifts leftward. E) None of the above is correct because the effect on the marginal revenue curve depends on whether the demand was initially elastic or inelastic.

In the 1930s the United States charged an average tariff rate

A) that cut its exports to other countries by 50 percent. B) that exceeded 50 percent. C) that was less than its average tariff rate in 2007. D) that was less than 2 percent.