Answer:
2
Step-by-step explanation:
just do the calculation for c = 0 and you will see yourself :
d = 1.50c = 1.50×0 = 0 wrong
d = 1.50c + 20.00 = 1.50×0 + 20.00 = 20.00 correct
d = 20.00c + 1.50 = 20.00×0 + 1.50 = 1.50 wrong
d = 21.50c = 21.50×0 = 0 wrong
