V=hpir^2
d/2=r
5/2/2.5
h=7
V=7pi2.5^2
v=7pi6.25
V=43.75pi
aprox pi=3.141592
V=137.44465
V=43.75pi ft^3 or aprox 137.44465 ft^3
SOLUTION
Given B is the midpoint of AC ABBC 1 and C is the midpoint of BD BCCD2 ie on adding 1 and 2 ART We get ABBCBCCD hence ABCD hence proved