Answer:
a). 1.218 m/s
b). R=2.8
Explanation:


Momentum of the motion the first part of the motion have a momentum that is:


The final momentum is the motion before the action so:
a).




b).
kinetic energy

Kinetic energy after

Kinetic energy before

Ratio =

Answer:
I know for sure that it's either A or B have a great day sorry I don't know which one completely
Answer:
The answer is gravity
Explanation: Hope this helps:)