Area of base is Circumference x or A = 25 x
A = 78.53981
Volume = Area of Base x Height or V = 78.53981 x 8
V = 628.32 Units
The volume of the cylinder is 628.32 units
See, pls, the suggested decision, if it's possible check the arithmetic part.
If i'm right m=3 because 15 divided by 3 is 5 so 9 divided by 3 is 3 :)