Respuesta :

4 hours for 18

7 hours for 25.50

Difference in hours: 7-4 = 3

Difference in cost: 25.50 - 18 = 7.50

7.50 / 3 = 2.50

A. They charge 2.50 per hour.

B. 2.50 x 4 = 10

18 - 10 = 8

The flat fee is 8 dollars

C. 8 + (2 x 2.50) = 13 dollars