An advertising company has developed a new ad for one of the national car manufacturing companies. the ad agency is interested in testing whether the proportion of favorable responses to the ad is the same between male adults versus female adults. it plans on conducting the test using an alpha level equal to 0.05. a sample of 100 adults of each gender will be used in the study. each person will be asked to view the ad and indicate whether they find the ad to be "pleasing" or not. given this, what is the appropriate null hypothesis?