1)A firm is studying the production times for two methods. The firm is satisfied with production method A and is prepared to continue using it if the mean delivery time for it is the same as or less than that of production B. However, if the firm finds that the mean delivery time for method B is less than that of method A, the firm will begin using method B. Assume that the independent samples show the following delivery time characteristics for the two production methods. Method ( n = 51 , x bar = 14.5days , S1 = 2.8 days ) Method B ( n= 30 , x bar = 12.5 days, S2 = 3.5 days ) What are the null and alternative hypotheses in this case? A) Ho : UA = 14 Ha : UB = 30 B) Ho : UA - UB <= 14 HA: UA - UB > 12.5 C) Ho : UA - UB >= 14 HA : UA - UB < 14 D) Ho : UA - UB >= 0 HA : UA - UB < 0 E) Ho : UA - UB <= 0 HA : UA - UB > 0 2) the calculated test statistic is A) z= 1.96 B) t= 1.73 C) z = 1.73 D) t = 2.67 E) z= 2.67 3) with alpha equal to .05, what is your conclusion for the hypotheses in part 1) , and what action do you recommend regarding the selection of a production method? A) reject Ho and continue with method A B) reject Ho and switch to method B C) do not reject Ho and continue with method A D) do not reject Ho and switch to method B D) none of the above