Technically it's a chemical change even though the process is reversible.
The thermosphere is a layer of Earth's atmosphere. The thermosphere is directly above the mesosphere and below the exosphere. It extends from about 90 km (56 miles) to between 500 and 1,000 km (311 to 621 miles) above our planet.
Answer:
C) Pressure will compress a gas, reducing its volume and giving it a greater density and concentration of particles.
Explanation:
At constant temperature, pressure and volume are inversely related.
P V = constant

As the pressure increases, the gas compresses, the particles come closer reducing the volume of gas.
As we know, with decrease in volume, density increases.


Thus, the pressure of a gas is directly related to concentration of particles. Increase in pressure causes increase in concentration of the particles.
Using
KE = ½mv² = ½×1500×19×19 = 270750 joules