volume of cone=1/3 time (area of base=circle) times height
iner cone=1/3 times pi times radius^2 times 3
diameter/2=radius
5/2=2.5
1/3 times 3.14 times 2.5^2 times 3=19.625=volume of inner cone
outer cone=14 times 3.14 times 2.5^2 times 1/3=91.5833
subtract
91.5833-19.625=71.9583
round
71.96 in^3