1. Preliminary analysis. (a) (0.5 points) The response variable (USRevenue) is quantitative. How about the explanatory variables? Which of the explanatory variables are quanti- tative? which categorical? (b) (1 points) Consider three (quantitative) explanatory variables: Budget, Opening and Theater. Use scatterplot to study the relationship between the response variable and each of these 3 explanatory variables. Comment. (c) (1 points) Provide correlation matrix among four variables, Budget, Open- ing, Theaters, and USRevenue. Is each quantitative explanatory variable highly correlated with the response variable? are explanatory variables highly correlated with themselves