To pay for his academic fees, Tarek, a college student, is selling a computer accessory to other students. His cost to purchase each piece is $77, and he is planning to sell the accessories for $104 each. Fixed costs for advertising amount to $420. (a) Compute the contribution margin. (b) Compute the contribution rate. (c) Compute the break-even point in units. (d) Compute the break-even point in sales dollars. (a) The contribution margin per unit is $ (Type a whole number.) (b) The contribution rate is %. (Round to two decimal places as needed.) (c) The break-even point in units is (Round up to the nearest unit.) (d) The break-even point in sales dollars is $ (Round to the nearest cent as needed.)