Answer:
The angle between the electric field lines and the equipotential surface is 90 degree.
Explanation:
The equipotential surfaces are the surface on which the electric potential is same. The work done in moving a charge from one point to another on an equipotential surface is always zero.
The electric field lines are always perpendicular to the equipotential surface.
As

For equipotential surface, dV = 0 so

The dot product of two non zero vectors is zero, if they are perpendicular to each other.
Answer:
c it is not accelerating on it's on but gravity pulls it there for velocity increases.
Answer: 0.04139m
Explanation:
First, we need to calculate the weight of the man which will be:
Weight = mass × acceleration due to gravity
Weight = mg
Weight = 92.5 × 9.8
Weight = 906.5N
Then, we calculate the force which will be:
F = kx
mg = kx
x = mg/k
x = 906.5/21900
x = 0.04139m.
The spring stretched for 0.04139m.