3 2 points The demand for a certain item is given by D(p) = - 2p + 40. The graph of the demand curve is shown below. What is the consumer surplus at a price of $50? The units of your answer should be thousand dollars. Round your answer to TWO decimal places and do not include units. D(P) q (thousand items) 40 30 20 10 5 10 15 20 25 30 35 40 45 50 55 60 P ($/item)