Answer:
I will answer a few questions so you can apply the same logic to the others
The volume of a sphere =
π

1.
We can see that the radius of the sphere is 5cm
Substitute the value into the equation for volume and solve for V
V =
* π *

V = 523.6

4.
The diameter is given to us as 6km. To find the radius we take half of this, 3km
Substitute the value into the equation for volume and solve for V
V =
* π *

V = 113.1

Hopefully that helps you with completing the rest!