Answer: A cylinder is a “circular prism”. To find its volume, like with any other prism, we just need to multiply the cross-sectional area by the length. Because the cross-section of a cylinder is a circle, we can calculate its area using the formula for the area of a circle: $A=\pi r^2$.
So in this case, the cross-sectional area is: $A=\pi 3^2=28.274…cm^2$
$V=28.274…\times 8=226.19 cm^3$ (2 d.p.)