A wet bicycle tire leaves a trace of water on the floor. The tire has a radius of 30 \text{ cm}30 cm30, start text, space, c, m, end text, and the bicycle wheel makes 333 full rotations before stopping.
How long is the trace of water left on the floor?

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.