Whenever you face the problem that deals with maxima or minima you should keep in mind that minima/maxima of a function is always a point where it's derivative is equal to zero.
To solve your problem we first need to find an equation of net benefits. Net benefits are expressed as a difference between total benefits and total cost. We can denote this function with B(y).
B(y)=b-c
B(y)=100y-18y²
Now that we have a net benefits function we need find it's derivate with respect to y.

Now we must find at which point this function is equal to zero.
0=100-36y
36y=100
y=2.8
Now that we know at which point our function reaches maxima we just plug that number back into our equation for net benefits and we get our answer.
B(2.8)=100(2.8)-18(2.8)²=138.88≈139.
One thing that always helps is to have your function graphed. It will give you a good insight into how your function behaves and allow you to identify minima/maxima points.
The value of 7 in 870,541 is 10,000
40 hours at 10.10 per hour = 404
10.10 x 1.5 = 15.15 overtime pay per hour
15.15 x 8 = 121.20
404 + 121.20 = $525.20 total
Answer:
The change division should put the unit to be dispensed with as an afterthought inverse of where it happens in the first inquiry.
540 inches * (1 yard/36 inches)
The inches best and base drop, abandoning you with the outcome in yards.