The function A (r)=ar2 gives the area of a circular object with respect to its radius r. Enter the inverse function r(A) to find the radius r required for area of A . Then estimate the radius of an
circular object that has an area of 80 cm2.
The inverse function is r(A) =
The radius of a circular object rounded to the nearest tenth is r (80) –
cm?

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.