Best answer gets brainliest. Here is a function `f` for Clare's moldy bread.

What is the average rate of change between f(4) and f(6)?​

the answer is y < -3 or   y > 3

-3y > 7 + 2

-3 y > 9

y < -3

the revenue of the fitness center, y, is the product of two factors: the number of members and the fee paid by each member. there are 320 members now, but number of members goes down by 10 for each $5 increase in fees, so if x is the number of $5 price increases then members is equal to (320 - 10x). since the fee is currently $45, and the fee increases by $5 for every price bump x, the fee is given by (45 + 5x). so, revenue y is given by y = (320 - 10x)(45 + 5x).