<span>when it returns to its original level after encountering air resistance, its kinetic energy is
decreased.
In fact, part of the energy has been dissipated due to the air resistance.
The mechanical energy of the ball as it starts the motion is:
</span>

<span>where K is the kinetic energy, and where there is no potential energy since we use the initial height of the ball as reference level.
If there is no air resistance, this total energy is conserved, therefore when the ball returns to its original height, the kinetic energy will still be 100 J. However, because of the presence of the air resistance, the total mechanical energy is not conserved, and part of the total energy of the ball has been dissipated through the air. Therefore, when the ball returns to its original level, the kinetic energy will be less than 100 J.</span>
Answer:
D. It is very small when compared to the universe
Explanation:
The Milky Way can be regarded galaxy which has Solar System in it. Milky way gives the description of appearance of galaxy from Earth, it is a hazy band of light that's been formed from the stars which can be visualized in the sky during the night, though it cannot be sorted by mere human eyes. Milky Way has existed for about 13.51 billion years with the radius of 52,850 light years. the Number of stars in milky way is about 100-400 billion. It should be noted that themilky way galaxy is a very large galaxy but It is very small when compared to the universe
.
C, electrons. Ion<span> of an </span>element has<span> the </span>same<span> nucleus, the </span>same number<span> of protons and neutrons, with a </span>different number<span> of electrons.</span>
The kinetic energy would be 53,775J:)