A temporary decrease in the price of oil would be considered a:

If Libby can produce 20 gallons of beer or 5 gallons of wine per hour, her opportunity cost of one gallon of beer is 4 gallons of wine

Indicate whether the statement is true or false

Producing leather creates external costs in the form of water pollution. The figure above illustrates the market for leather. In the absence of any government regulation, how many tons of leather will be produced?

A) 0 tons B) 200 tons C) 300 tons D) more than 300 tons E) None of the above answers is correct.