A businessman buys a certain commodity at P23 per unit and sells them at P39 per unit. His fixed cost is P3,500. Due to stiff competition, the sale of the product began to decline. The selling price decreased by 4% of the units sold. The variable and fixed cost remain constant. a) Represent the new selling price function. b) Determine the TR, TC and Profit function. c) Find the BEP quantity revenue. d) What is the profit at a sale volume of 120 units.