Gloria Meehan is considering opening a window tinting business. She estimates that the following costs will be incurred during the first year of operations: Rent, $6,500; depreciation on equipment, $7,250; Wages, $4,250 (wages vary with production, estimate is based on 625 windows tinted in the previous year); tinting, $4 per square foot. Each window tinted takes 5 square feet of tint. Gloria anticipates that she will tint each window for a retail price of $63 each. Instructions a) Determine variable costs per unit and total fixed costs. b) Determine the break-even point in number of windows to be tinted. c) How many windows need to be tinted to earn income of $21,000?