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.
Human error (average human reaction time is .2 seconds)
Benthos
Option b is the answer
Answer:
Fnet = 0
Explanation:
- Since the block slides across the floor at constant speed, this means that it's not accelerated.
- According Newton's 2nd Law, if the acceleration is zero, the net force on the sliding mass must be zero.
- This means that there must be a friction force opposing to the horizontal component of the applied force, equal in magnitude to it:

- In the vertical direction, the block is not accelerated either, so the sum of the normal force and the vertical component of the applied force, must be equal in magnitude to the force of gravity on the block:

⇒ 169 N + Fn = Fg = 216 N (3)
- This means that there must be a normal force equal to the difference between Fappy and Fg, as follows:
- Fn = 216 N - 169 N = 47 N (4)