Using the given equation:
di = 20.0 * 10.0 / 20.0 - 10.0
di = 200/10
di = 20.0 cm
The answer is A.
The initial kinetic energy of the car is

Then, the velocity of the car is decreased by half:

so, the new kinetic energy is

So, the new kinetic energy is 1/4 of the initial kinetic energy of the car. Numerically:
True
In fact, the weight of an object on the surface of the Earth is given by:

where m is the mass of the object and

is the gravitational acceleration on Earth's surface. If we use the mass of the object, m=3.0 kg, we find
Answer:
D. gravitational potential energy
Explanation:
That only happens when the temperature is below freezing and the air around the ice is dry.