5. Believed to be among the preproduction factors driving success were budget (which expresses both the cost of the film and the quality of the actors as expressed by their fee), genre (comedy vs. non-comedy), MPAA rating (R-rated vs. other rating), and audiences' familiarity with the story (whether the film is a sequel or an adaptation of a known story). a. Based on the described beliefs, determine a sound regression model predicting total U.S. box-office gross of movies prior to production. b. Drop all variables from the regression that are not significant at a 10 percent level of significance. Report the final regression. c. Holding all other explanatory variables in your regression fixed, which movies have higher total U.S. gross, those that are a sequel or those that are not