Problem 3: According to the following figure, A P 50 Price (dollars) TO 0 4,000 Quantity a) demand is unitary elastic at P - b) demand is elastic for all the prices between and c) demand is inelastic for all the prices between and d) marginal revenue is zero at Q - e) marginal revenue is greater than zero for all the quantities between and () marginal revenue is less than zero for all the quantities between and