A store has issued two different coupons for its customers to use. One coupon gives customers $20 off their purchase price, and the other coupon gives customers 20% off of their purchase. The store allows customers to use both coupons and choose which coupon to apply first. For this context, ignore sales tax. Let f be the function that inputs a cost (in dollars) and outputs the cost after applying the \"$20 off\" coupon, and let g be the function that inputs a cost (in dollars) and outputs the cost after applying the \"20% off\" coupon. a. A customer purchases an item for $120 and asks the cashier to apply the \"$20 off\" coupon first, followed by the \"20% off\" coupon. What is the cost of the item after the two coupons are applied? $ Preview b. A customer purchases an item for $120 and asks the cashier to apply the \"$20 off\" coupon first, followed by the \"20% off\" coupon. Use function notation to represent the cost of the item (in dollars) after the two coupons are applied. Preview c. A customer purchase an item for $120 and asks the cashier to apply the \"20% off\" coupon first, followed by the \"$20 off\" coupon. What is the cost of the item after the two coupons are applied? Preview d. A customer purchases an item for $120 and asks the cashier to apply the \"20% off\" coupon first, followed by the \"$20 off\" coupon. Use function notation to represent the cost of the item in dollars) after the two coupons are applied. Preview