Giselle bought a dress for $35 and three t-shirts. She used a coupon for $2.50 off each t-shirt. The total cost can be modeled by the expression 35 + 3(n - 2.5) . What does n - 2.5 represent? A. the number of t-shirts purchased
B. the total cost of the t-shirts
C. the total cost of a t-shirt after the coupon is applied
D. the amount Giselle saved by using a coupon

Ascientist has 50 grams of a radioactive element. the amount of radioactive element remaining after t days can be determined using the equation (1) after two days the scientist receives a second shipment of 50 grams of the same element. the equation used to represent the amount of shipment 2 remaining after t days is 10) - 50 which of the following is an equivalent form of the expression for the amount remaining in shipment 2? what’s the answer?