Tappan Farms is a local organic farm that sells Tomatoes, Lettuce, and Carrots at the Ann Arbor Farmers Market each week. Their truck can hold 20 bins of produce. One bin can hold 10 pounds of Tomatoes, 2 pounds of Lettuce, or 15 pounds of Carrots. The truck makes one trip to the farmers market each week, so they can only sell what they can fit on the truck. Tomatoes sell for $2 per pound, Lettuce sells for $3 per pound, and Carrots sell for $3 per pound. The growing and harvesting costs are $1 per pound for Tomatoes, $0.50 per pound for Lettuce, and $2.50 per pound for Carrots. Assume that Tappan cannot mix produce in a bin, and that maximum demand at the farmers market for each vegetable is 150 pounds of Tomatoes, 30 pounds of Lettuce, and 225 pounds of Carrots. Given this information, how should Tappan load the truck to maximize profits at the farmers market.

How many bins of Tomatoes?

How many bins of Lettuce?

How many bins of Carrots?

The truck costs $40 to drive round-trip to and from the farmers' market. However, for an extra $10, Tappan can haul a trailer, expanding capacity by an additional 10 bins. How much additional profit can the farm earn by pulling the trailer?