1. A farmer can sell his potatoes for $8 per bushel today, but this price is dropping by 5¢ per day. The farmer estimates that his crop in the field would amount to 1300 bushels if harvested today and...

1. A farmer can sell his potatoes for $8 per bushel today, but this price is dropping by 5¢ per day. The farmer estimates that his crop in the field would amount to 1300 bushels if harvested today and that it is increasing at the rate of 10 bushels per day. Express the farmer's income from the sale of the potatoes as a function of the number of days he waits before harvesting and selling the crop.