Answer:
p ^ q
I promise you this is right but it's quite long to explain.
So it’s $15 per month so that is what you are gonna multiply by x. You start out with $75 so that’s the initial fee. 15x + 75 is your expression.
It means that the equations answers are
odd (numbers 1,3,5 ,7,9)
even numbers (2,4,6,8,10)
or neither (0 or infinity)