Circle of intersection of two spheres. (1 Viewer)

[kractus]

Unsure how to word part a and for part b, I don't know where to start kinda. I tried to substitute and other methods but got nowhere

 

[jimmysmith560]

Would the following information and working help?

Part (a):

The circle of intersection will be perpendicular to the axis the spheres are centred on as both spheres centre on the 𝑧-axis, one at (0, 0, 0) and the other at (0, 0, 5).

The sphere of intersection between the two spheres will be parallel to the 𝑥𝑦-plane.

Part (b):

 

[kractus]

Yes thank you!