From the problem :

In multiplying expressions with the same bases, the exponent will be added accordingly.
For example :

the exponent of a are m and n, and the product will be a raised to the sum of m and n.
Applying this to the problem, we have :

The answer is d. 6^-1
Answer:
Step-by-step explanation:
Volume = pi·(r^2)*h
r = radius = (5x+4)
h = height = (2x+5)
Volume = pi·(r^2)
Volume = pi·(5x+4)^2*(2x+8)
Volume = pi·(25x^2+40x+16)*(2x+8)
Volume = pi·(50x^2+80x+32+200x^2+32x+128)
Volume = pi·(250x^2+112x+160)
9 times 52 = 468 hope that helped!!
The way to determine this is to know that 1 foot is 12 inches (so 2 is 24)
Now the ration that would determine the scale factor of the room is 1:24 (1 inch for every 24 inches)
So the scale factor is 1:24
Now to determine the area we multiply the numbers we have by 2 and change the inches to feet (I hope that makes sense to you, it does to me, I'll show you)
10.25 * 2 = 20.5 ft.
8 * 2 = 16 ft.
now we know the dimensions of the room so we need to find the area.
A=B*H
20.5 * 16 = 328
so the area of the room is 328 ft.²