The ordering and transportation cost c for components used in a manufacturing process is approximated by the function below, where c is measured in thousands of dollars and x is the order size in hundreds. c(x) = 12 1 x + x x+3 (a) verify that c(3) = c(6). c(3) = 10 correct: your answer is correct. c(6) = 10 correct: your answer is correct. (b) according to rolle's theorem, the rate of change of the cost must be 0 for some order size in the interval (3, 6). find that order size. (round your answer to the nearest whole number.)

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.