Can you please answer the a and the b?

a) Epot = 17658 [J]

b) v = 76.72 [m/s]

Explanation:

Potential energy is defined as the product of mass by gravity by height.

where:

Epot = potential energy [J]

m = mass = 6 [kg]

g = gravity acceleration = 9.81 [m/s²]

h = elevation = 300 [m]

Now replacing:

b)

The energy is conserved, that is, the potential energy is converted into kinetic energy as the car descends.

where:

v = velocity = 2 [m/s]

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.