Answer:
a) 
b) 
Explanation:
Given:
mass of the ball, 
horizontal velocity of the ball, 
mass of the person, 
a)
<u>Using the law of conservation of momentum:</u>



b)
Given:
- rebound velocity of the ball,

Using conservation of momentum,



Answer:
evaporation, melting, freezing
Explanation:
matter is a solid, gas, or liquid
evaporation turns a liquid to gas
melting changes a solid to liquid
freezing changes a liquid to a solid
That was his student, Johannes Kepler.