During swim practice, an olympic swimmer is required to complete three swimming intervals, in this order: warm-up freestyle, sprint freestyle, and cool-down breast stroke. after he completes each interval, he rests for three minutes. sketch a graph that represents the swimmers’ interval times with respect to swimming speed. assign the x- and y-axes with appropriate labels. you may use description words instead of numbers to label the graph.

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.