The fastest measured pitched baseball left the pitcher's hand at speed of 45 m/s. if the pitcher was in contact with the ball over a distance of 1.50 m and produced constant acceleration, (a.) what acceleration did he give the ball and (b.) how much time did it take him to pitch it? i need answers you

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.