Answer: 6259.9 cu. cm.
For 6)
Volume, V, for a cylinder:
generally V = A * h = πr^2h, therefore,
V1 = πr1^2h for the volume enclosed by C1
V2 = πr2^2h for the volume enclosed by C2
V = V1 - V2 for the volume of the solid, the tube.
V = π(r1^2 - r2^2)h
