1.
The energy in a mechanical system is determined by adding the potential and kinetic energy together.

total
massive
2.
The initial energy is equal to zero because the starting point is set at zero height to make things easier.

kinetic
potential
3.
In the example, the final kinetic energy is determined to be because at the peak height, the ball instantaneously stops.

positive
zero
negative
4.
In this system, potential and kinetic energy are proportional.

inversely
directly

The system has an energy that can be conserved in the system, and when work is performed, the energy has been converted to working energy.

The following sentences can be completed as:

Total energy = Potential energy + Kinetic energy

For more information about kinetic and potential energy, refer to the link:

link

1) total, 2) potential, 3) zero, 4) inversely.

Explanation:

1) The total energy in a mechanical system is determined by adding the potential and kinetic energy together.

2) The initial potential energy is equal to zero because the starting point is set at zero height to make things easier.

3) In the example, the final kinetic energy is determined to be zero because at the peak height, the ball instantaneously stops.

4) In this system, potential and kinetic energy are inversely proportional.

it would be a gas formation