Answer:
Upper disk rotates at a constant angular velocity. The velocity at any height from stationery disk, say at x metres
where v is tangential velocity at radius r from the centre of disk
The radial component of velocity is given as
The z component of velocity is also given as
W=0
Total velocity, 
Inelastic.
If it was elastic, they'd bump right off each other. But since they've been locked, or stuck together, this is inelastic.
It is a reflecting telescope and a compound microscope. I know this for sure
Answer:
wind
Explanation:
wind is the only one of those onto that list that is a renewable source
