Answer:
39.25 cubic feet of paint will be needed by Ellis.
Step-by-step explanation:
Volume of a cylinder:
The volume of a cylinder of radius r and height h is given by:

How much paint will Ellis need to paint all the surfaces of the 10 fenceposts?
This is the combined volume of these 10 fenceposts.
They are each 5 feet tall and have a diameter of 1 foot.
Radius is half the diameter, so
. Also 
10 fenceposts:
Each has the same volume, so:

39.25 cubic feet of paint will be needed by Ellis.
We notice a factor of 2x in both
2x(5x^2+4x-3)
trial and error
(5x-3)(x+1) yeilds 5x^2+2x-3, nope
(5x+3)(x-1) yeilds 5x^2-2x-3, nope
(5x-1)(x+3) yeilds 5x^2+14x-3, nope
(5x+1)(x-3) yeilds 5x^2-14x-3, nope
simplest form is
2x(5x^2+4x-3)
Minus them both to get your answer
H= 445.36
because you bring the 86.43 over to the 531.79. which would make 86.43 a negative number. so you subtract 531.79 by 86.43