Getting an annual flu shot is a way to reduce the chances of not only contracting influenza, but also spreading it to other people. In this sense, getting an annual flu shot is reducing ________ of spreading a contagious disease

A surplus in our balance of payments causes the dollar to __________, which causes the surplus to __________

A) appreciate; increase B) appreciate; decrease C) depreciate; increase D) depreciate; decrease

An externality occurs whenever

A) private costs are the same as social costs. B) private costs are the same as internal costs. C) private costs diverge from social costs. D) private costs plus internal costs equal social costs.