Suppose air travel is a normal good. Also, jet fuel used in commerical airplanes is an input in the production of air travel. If consumers' incomes go up and the price of jet fuel falls, which of the following can we predict about the quantity and price (airfares) in the market for air travel?
A.) Quantity will go up; change in price is ambiguous
B.) Quantity will fall; price will go up
C.) Quantity will go up; price will fall
D.) Quantity will fall; change in price is ambiguous