The market demand curve is ____ and the demand curve for a single firm in a competitive market is ____

If the nominal exchange rate between the American dollar and the Canadian dollar is 0.89 Canadian dollars per American dollar, how many American dollars are required to buy a product that costs 2.5 Canadian dollars?

A) $1.32 B) $2.23 C) $2.75 D) $2.81

The slope of a line

a. can only be calculated for straight lines b. varies at different points along a straight line c. indicates whether or not there is a causal relationship between variables d. is independent of the units of measurement used e. indicates how much the vertical variable changes for a given change in the horizontal variable