If the percentage change in the quantity demanded of a good equals the percentage change in price, price elasticity of demand is:

An environmental protection agency in Eduland has launched a campaign against the use of plastic bags. This is an example of ________

A) backward induction B) indoctrination C) anchoring D) sniping

When a private transaction imposes costs on others not directly involved in the transaction, _____

a. a negative externality exists b. a positive externality exists c. the good involved in the transaction is a club good d. the tragedy of commons problem arises e. a free rider problem arises