John and 3 friends are going out for pizza for lunch. they split one pizza and 4 large drinks. the pizza cost $13.00. after using a $6.00 gift certificate, they spend a total of $13.20. write an equation to model this situation, and find the cost of one large drink. a. 3d + $13.00 – $6.00 = $13.20; $2.07 b. 4d + $13.00 – $6.00 = $13.20; $1.55 c. 4d – $13.00 + $6.00 = $13.20; $6.73 d. 4d + $13.00 – $6.00 = $13.20; $1.60