18. Bombay Charlie's, a fast food Indian restaurant, is thinking about adding a certain spice to their chicken curry dish to attract more customers. The restaurant manager has decided to add the spice if more than 80% of his customers prefer the taste of the chicken curry with the spice added. Sixty-five customers are randomly selected to participate in a blind taste test. Fifty-four of these customers prefer the chicken curry with the added spice. a. Find the P-value for the hypothesis test that the manager will perform to decide if more than 80% of the customers prefer the taste of the chicken curry with the added spice. b. Do the data suggest that more than 80% of the customers prefer the curry with the new spice at a = 0.05? 19. The news program for KOPE, the local television station, claims to have 40% of the market. A random sample of 500 viewers conducted by an independent testing agency found 192 who claim to watch the KOPE news program on a regular basis. a. Find the P-value for testing the hypothesis that the news program for KOPE does not have more than 40% of the market as it claims. b. Is there sufficient evidence to reject the hypothesis that KOPE does not have at least 40% of the market at a significance level of 0.05? 20. The length of time that a storm window will last before beginning to leak is of interest to a window manufacturer who wishes to guarantee his windows. He believes that more than 50% of the windows will last at least four years. To research this. 931 windows, which were installed at least four years ago, are randomly selected and checked for leakage. Five hundred of the windows are found to still be leak-free. a. Find the P-value for testing the hypothesis that more than 50% of the windows will be leak-free in four years. b. Does the sample support the hypothesis that more than 50% of the windows will be leak-free in four years at a = 0.05? 21. In order to discourage soldiers from smoking, the Pentagon raised the price of cigarettes by $4 a carton in October of 1996. This increased the average price of a carton of brand-name cigarettes to $17.50, an increase of about 30%. Prior to the price increase, about 32% of military personnel smoked, as opposed to 25% of all adult Americans. Suppose that following the price increase, a random sample of military personnel is selected to determine smoking habits. With a = 0.05, can we conclude that the price increase was effective in decreasing the percentage of smokers if 50 of the 200 military personnel sampled smoke? Hu