Bill spent $60 of fertilizer and weed killer for his lawn. Each pound of fertilizer cost 75 cents, and each ounce of weed killer cost $2.50. Which of the following equations represents the relationship
between the number of pounds of fertilizer Bill bought, x, and the number of ounces of weed killer
he bought, y?

a) y = -3/10x + 24
b) y = -3/4x + 60
c) y = -5/2x + 60
d) y = -10/3x + 80