Gibson Entertainment sells souvenir T-shirts at each rock concert that it sponsors. The shirts cost $15 each. Any excess shirts can be returned to the manufacturer for a full refund of the purchase price. The sales price is $29 per shirt. Required . What are the total cost of shirts and cost per shirt if sales amount 00, 4,000, 4,500, or 5,000? 3,000 3,500 & 5.000 Number of shirts sold Total cost of shirts Cost per shirt