Can someone plz answer this correctly and quickly.
a cylinder shaped water tank has a diameter of 8m and height of 20m. what volume of water does the tank contain when it is 60% full? use 3.14 to approximate pi.

V = h

1. Find the radius. 

8/2 = 4

2. Square the radius.

= 16

3. Multiply that by pi.

3.14 * 16 = 50.24

4. Multiply that by the height.

50.24 * 20 = 1004.8

5. Now find 60% of that.

1004.8 * 0.6 = 602.88

V = 602.88 

Honestly, it's been a while since I've done this, but I believe this is the answer.

(1/x + 1)^2 + 6 (1/x + 1) +5