A professional services firm is investigating yield management as a means of taking advantage of unused capacity. Analysts for this firm estimate a demand curve for the firm's service, which is sold by the hour. Points on this demand curve include 9000 hours at the current rate of $60 per hour, 9500 hours at $55, 10,000 hours at $50, and 10,500 hours at $45. Based on this demand curve, what price point would be best for the firm, if its objective is maximum revenue?