C. Because protons are the identity of the atom.
I think it’s A.) it explains why the universe is made up of matter
Answer:
The velocity of ball and man after catching ball is
Explanation:
Since there is no friction and no external force the momentum is conserved .
Here when man catches ball then man and ball move with common velocity .
Let the final common velocity be ,
Given that mass of the ball is =
Given that mass of man is
Initial velocity of ball =
Now considering momentum conservation
One is speed and the other distance. i think.... hopefully this helps. <span />