Answer: 11.4
Step-by-step explanation:
change to numbers 
simplify 
30,00 watts.
Think of the metric system like this: K H D B D C M
Now. you have kilo at the begining and milli at the end. To transition from left to right you multiply by 10 each time. To transition from right to left, you divide by 10 each time.
First of all, it's not pie. It's pi.
Now, the problem.
Radius is always 1/2 x d (d meaning diameter)
That gives us 5.
The formula is 3.14 x 5^2(h/3)
If you solve it from left to right, you get 130.83
Answer:
It would probably be 15 actually
