Answer:
the kinetic energy the bat can give to a ball is 2,025 J.
Explanation:
Given;
mass of the bat, m = 2kg
velocity of the bat, v = 45 m/s
The kinetic energy the bat can give to a ball is calculated as;

Therefore, the kinetic energy the bat can give to a ball is 2,025 J.
If the velocity is decreased by half, then Kinetic energy will reduced to it's 4 times,
= 1.9 * 10³ / 4
= 4.75 * 10²
In short, Your Answer would be Option B
Hope this helps!
Explanation:
As the given spheres are connected by a thin wire so, the potential on the spheres are the same.
......... (1)
Hence, total charge will be as follows.
= Q = -95.5 nC .......... (2)
Using the above two equations, the final equation will be as follows.

and, 
Hence, we will calculate the charge on sphere B after the equilibrium is reached as follows.

= 
= 82.714 nC
Thus, we can conclude that the charge on sphere B after equilibrium has been reached is 82.714 nC.