Farmer Jones grows sugar. The total revenue, marginal revenue, total cost, and marginal cost of producing various quantities of sugar (bushels in 1000s) are presented in the table below. Output Total Revenue Marginal Total Marginal (bushels in 1000s) Revenue Cost Cost 0 $0 0 42 42 60 60 84 42 100 40 UAUN- 126 42 120 20 168 42 160 40 210 42 240 80 252 42 340 100 Suppose the market for sugar is perfectly competitive. To maximize profits, farmer Jones should produce thousand bushels of sugar. (Enter a numeric response using an integer.) At that level of output, farmer Jones will earn profit of $