Dwayne is selling hamburgers and cheeseburgers. He has 100 burger buns. Each hamburger sells for $3, and each cheeseburger sells for $3.50. Which system of inequalities represents the number of hamburgers, h, and the number of cheeseburgers, c, he must sell to have sales of at least $80? h + c ≤ 80 3h + 3.5c ≤ 100 h + c ≤ 80 3h + 3.5c ≥ 100 h + c ≤ 100 3h + 3.5c ≤ 80 h + c ≤ 100 3h + 3.5c ≥ 80