Please help, 15 points + brainliest!

Answer:
C
Step-by-step explanation:
Volume of a sphere is given by
V = 4/3 pi r^3
where r is the radius
The radius is 6.5
V = 4/3 *pi * (6.5)^3
V = 4/3 pi *274.625
V =366.1666667 *pi
V = 366.16(repeating) pi ft^3