9. A person is sitting on a 30 foot pier overlooking the ocean. His eye level is 3 feet above the pier. He sees a whole surface in the ocean. If the angle of depression of the whale is 20", how
far is the whale from his eyes?

The john deere company has found that revenue,in dollars, from sales of heavy-duty tractors is a function of the unit price p, in dollars, that it charges. if therevenue r is r(p)= -1/2p^2 +1900pa)how much revenue will the company generate if they sell 700 tractors? b) how many tractors does the company want to sell to maximize the revenue?