Harold bought 3 pounds of red apples and 4.2 pounds of green apples from the grocery store, where both kinds of apples are $1.75 a pound. how much money did harrold spend on apples

Harold spent $12.60 total.

Steps:
First multiply the ammount of pounds (3 & 4.2) by the price ($1.75). For instance, multiply 3 × $1.75 to get $5.25. Then multiply 4.2 × $1.75 to get $7.35. Finally, add $7.35 to $5.25 to get $12.60.

I'm pretty sure it's b). i try drawing the functions out and b is the one that stands out or isnt a "line"