Find the radius of the sphere using the known surface area, then use that value to calculate the volume.
Here is how:
surface area = 4 times pi times the radius squared.
surface area = 4(pi)r^2
90790 = 4 x 3.14 x r^2
Therefore r = The square root of (90790/(4 x 3.14)
Therefore r = 85.02
Now use this value of r to find the volume of the sphere.
volume of a sphere = 4/3 times pi times r cubed
volume = 4/3 x 3.14 x r^3
volume = 4/3 x 3.14 x (85.02)^3
Volume = 2,572,952
Second Part of Question:
Answer: Find the radius of the sphere using the known volume, then use that value to calculate the surface area.
Here's how:
volume of a sphere = 4/3 times pi times r cubed
volume = 4/3 x 3.14 x r^3
1200 = 4/3 x 3.14 x r^3
r = the cubed root of 1200/(4/3 x 3.14)
r = 17.127
Now use this value of r to find the surface area of the sphere.
surface area = 4 times pi times the radius squared.
surface area = 4(pi)r^2
surface area = 4 x 3.14 x (17.127)^2
surface area = 3684.277