Lance went to the hardware store to buy a saw and a paint sprayer, and while he was in the checkout line, he also threw some screws and some hinges into his shopping cart. which two products were impulse purchases? a. the saw and paint sprayer b. the screws and hinges c. the saw and hinges d. the screws and paint sprayer

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.