Answer:

Explanation:
- We have to make a hollow sphere of inner radius
and outer radius
.
Then the mass of the material required to make such a sphere would be calculated as:
Total volume of the spherical shell:

And the volume of the hollow space in the sphere:

Therefore the net volume of material required to make the sphere:


- Now let the density of the of the material be
.
<u>Then the mass of the material used is:</u>


The magnitude of the average force exerted on the ball by the wall is calculated below.
The average force exerted by the ball on the wall is 3 N
Explanation:
Given:
mass of the ball (m)=0.10 kg
speed (v) =3.0 m/s
time taken(t) =0.01 seconds
To calculate:
Average force(F) exerted by ball on the wall
We know;
F=(m×v)÷t
F=(0.10×3.0)÷0.01
<u><em>F=3 N</em></u>
Therefore the average force exerted by the ball on the wall is 3 N
Visibly you can see that the two copper are different sizes so the mass and volume are different. No information is given about the temperature but they are side by side so you can assume they're both room temp. The density is a ratio of mass per volume. The density will remain the same unless the two are different purities or physical states.
Through a dam... hope this helps:)