Agas station sells a coffee mug filled with coffee for $3. for each refill, using the same mug, the gas station charges $1.25 for the coffee. if y represents the total cost and x represents the total number of filled coffee mugs purchased, which function rule describes this pattern? a y = 1.25 (x+1) +3 b y = 1.25 (x+1) +3 c y = 3 + 1.25x d y = 3 (x-1) - 1 .25