A local courier service estimates its monthly operating costs to be $1500 plus $0.85 per delivery. The service generates revenue of $6 for each delivery. Let x = the number of deliveries in a given month. The function C(x) = .85x + 1500 represents the operating cost. The function R(x) = 6x represents the revenue generated. Knowing that profit = revenue - cost, write a function, P(x), that represents the monthly profits for making x deliveries per month.