A garbage incinerator charges $25, plus $10 per ton, to incinerate a truckload of garbage. The average cost per ton (in dollars) for 10n + 25 incinerating n tons of garbage is given by A(n)=- a. Use the accompanying graph to determine whether the average cost per ton is increasing or decreasing as the size of the load increases. b. A company uses trucks with capacities of 9, 16, and 21 tons. What is the average cost per ton for each truck? Average cost perton (3) 60- 40- 20+ 10 20 30 Truck capacity (tom) b. The average cost per ton for a 9 ton truck is (Simplify your answer. Round to two decimal places as needed.) The average cost per ton for a 16 ton truck is (Simplify your answer. Round to two decimal places as needed.) The average cost per ton for a 21 ton truck is. (Simplify your answer. Round to two decimal places as needed.)