The cheetah runs 2 meters/sec faster than the gazelle. Eventually the cheetah will overcome the gazelle. Since distance = rate times time, time = distance/rate.
Vcylinder=hpir^2
Vsphere=(4/3)pir^3
Vcone=(1/3)hpir^2
Vcylinder=15*pi*5^2=375pi in^3
Vsphere=(4/3)*pi*6^3=288pi in^3
Vcone=(1/3)*15*pi*8^2=320pi in^3
greatest is Vcylinder at 375pi in^3
answer is A (cylinder)