8 21/100 is the mixed number for8.21
I’ve attached my work...
Hope it helps! Have a nice day :)
Work is provided in the image attached.
Although you did not include units, I just used centimeters.
However, if there were no units, then just put your answer.
If you do not understand my work,
please ask me in the comments below.
Volume = 1/3 pi r^2 h
= 1/3 * 10^2 *81 pi
= 2700 pi units^3
Its C