Question

What is the approximate volume of a cylinder with a diameter of 4 cm and I height of 10 cm

Answer 1

$\pi r^{2} h = \pi 2^{2}(10) = 125.66$ cm

Answer 2

V≈125.66
V=$\pi$r²h
r=d/2
So 4/2=2
plug it in 
V=$\pi$2²*10
V=$\pi$40
V≈125.66