What is the relationship between the marginal product of labor and the value of the marginal product of labor?

Paulette owns a pizza parlor. Her total cost schedule is in the above table. Her total variable cost of producing four pizzas per hour is

A) $20. B) $49. C) $51. D) $71. E) Some amount, but more information is needed to determine this total variable cost.

In economic terms, tariffs are preferred to quotas because

A) domestic manufacturers gain more producer surplus. B) there is less loss of consumer surplus. C) tariffs are easier to administer. D) quotas create a greater production inefficiency. E) given the way quotas are usually administered, tariffs cause a smaller net national welfare loss.