An outboard motor has an initial price of $3,200. A service contract costs $300 for the first year and increases $100 per year thereafter. The total cost of the outboard motor (in dollars) after n years is given by

C(n) = 3,200 + 250n + 50n² n ≥ 1

(A) Write an expression for the average cost per year, C1n2, for n years.

(B) Graph the average cost function found in part (A).

(C) When is the average cost per year at its minimum? (This time is frequently referred to as the replacement time for this piece of equipment.)