7. Griffith also knew the even stronger version of that age-old Hollywood wisdom which stated that 25 percent of a movie's U.S. box-office gross revenue came in during the opening weekend. All this conventional wisdom made him curious to examine the relationship between total U.S. box-office gross and opening weekend box-office gross. a. Run a simple linear regression predicting total U.S. box-office gross from opening weekend box-office gross. b. If the stronger version of that age-old wisdom were true, that is, if indeed 25 percent of a movie's U.S. box-office gross revenue came in during the opening weekend, what would the value of the slope coefficient in the linear regression model have to be? c. Can the age-old wisdom be rejected based on the simple linear regression? d. Critique the statistical analysis in part (c). e. Determine a sound regression model predicting total U.S. box-office gross from opening weekend box-office gross. f. Examine the validity of the age-old wisdom using the new regression. g. What proportion of the variation in total U.S. box-office gross revenue can be explained by variation in the opening weekend box-office gross revenue