A person operates a delivery service in a southern city. His start-up costs amounted to $2400. He estimates that it costs him (in terms of gasoline, wear and tear on his car, etc.) $2.00 per delivery. He charges $4.50 per delivery. Let x represent the number of deliveries he makes. (a) Express the cost C as a function of x, where x represents the quantity of items as given. (b) Express the revenue R as a function of x (c) Determine the value of x for which revenue equals cost. (d) Graph the equations y = C(x) and y = R(x) on the same axes, and interpret the graph. (a) C(x) = (C in dollars)