I'm not too sure of the relationship. I know if the demand decreased, then the marginal revenue would decrease and the profit maximizing level of output would also decrease.

Corn is produced in a perfectly competitive market. The demand for ethanol increases. This will cause the individual corn farmer's marginal revenue to and their profit-maximizing level of output to Q A. increase; increase O B. increase; decrease O C. decrease; increase 0 D. decrease; decrease O E. None of the above