Answer:
90 N
Explanation:
The electrostatic force between two charges is given by:

where
k is the Coulomb's constant
q1, q2 are the two charges
r is the separation between the charges
In this problem we have
q1 = q2 = 0.005 C
r = 50 m
So the electrostatic force is

Sometimes they are the same in physics. it depends how the question is worded but speed comes before velocity. If you take the derivative of speed you will end up with its velocity. The same goes when you take the integral of velocity.
First solve the potential energy of the biker. using the fomula:
PE = mgh
where m is the mass of the object
g is the acceleration due to gravity ( 9.81 m/s2)
h is the height
PE = 96 kg ( 1120 m ) ( 9.81 m/s2)
PE = 1054771.2 J
then power = Work / time
P = 1054771.2 J / ( 120 min ) ( 60 s / 1 min)
P = 146.5 W