Can you show me step by step how this problem is answered; 14.9 (1) Karl Kapitalist is willing to produce p/2 - 20 chairs at every price, p > 40. At prices below 40, he will produce nothing. If the price of chairs is $100, Karl will produce 30 chairs. At this price, how much is his producer's surplus? 12(60 × 30) = 900.