Last year Christine worked as a consultant. She hired an administrative assistant for $15,000 per year and rented office space (utilities included) for $3,000 per month. Her total revenue for the year was $100,000. If Christine hadn't worked as a consultant, she would have worked at a real estate firm earning $40,000 a year. Christine's opportunity cost of working as a consultant last year was ________.

As more people imported cars from abroad, service facilities became widely available. This increased the value of imported cars to those who owned one. This is an example of a(n) ________

A) pecuniary externality B) network externality C) moral hazard D) adverse selection

Suppose a monopolist's costs and revenues are as follows: ATC = $50; MC = $40; MR = $45; P = $55. The firm should

A) increase output and decrease price. B) decrease output and increase price. C) not change output or price. D) shut down.