Suppose you were to collect data for each pair of variables. You want to make a scatterplot. Which variable would you use as the explanatory variable, and which as the response variable? Why? What would you expect to see in the scatterplot? Discuss the likely direction and form. a) T-shirts at a store: price each, number sold. b) Real estate: house price, house size (square footage). c) Economics: interest rates, number of mortgage applications. d) Employees: salary, years of experience.