lavontaysimmons lavontaysimmons 20-03-2017 Mathematics contestada The total cost of gasoline varies directly with the number of gallons purchased. Gas costs $1.89 per gallon. Write a direct variation to model the total cost c for g gallons of gas. a. g = 1.89c b. c = g + 1.89 c. c = 1.89g d. c = g