1/3*3.14*5²*9
=(1/3)*9*(3.14*100/4)
=3*(314/4)
=3*78.5
=3*(80-1.5)
=240-4.5
=235.5
(1/3)*3.14*6²*4
=(1/3)*6*6*4*3.14
=2*6*4*3.14
=(50-2)*3.14
=157-6.28
=150.72