A farmer sells peaches and kiwis at a farmers market. The peaches sell for $3.50 per pound and the kiwis sell for $2.75 per pound. The farmer's truck can carry 1,800 pounds of fruit.
If the farmer sells all 1,800 pounds of fruit that he brings to the market, what is the maximum and what is the minimum amount of money he can earn? Provide support for your answer.