A man is looking up at a bird perched on top of a tree. His line of sight to the bird is at an angle of elevation of 28°. If the man's eyes are 6 feet off the ground and he is
standing 14 feet away from tree, how far up the tree is the bird perched?

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.