When the contracting gas and dust from nebula become so dense and hot that nuclear fusion starts
Answer:
Option A, B, C and D
Explanation:
First to all, we need to remember something. Mercury is the first planet to our solar system, therefore, it's the closest planet to the sun. Because of this, temperatures of that planet are way too high.
Mercury has a very thin atmosphere so it barely exists. It also has a low gravity and receives large gusts of solar winds from the Sun, that's why it has high temperature, and therefore, it's escape velocity is very low too.
Of course, it's one of the smallest planets in our solar system, so,the atmosphere of Mercury is unstable and constantly shifting. As the atmosphere’s materials are being made, they are also being taken away at the uppermost layers due to solar winds. The composition of the atmosphere can also change as you move across the planet.
I'd be happy to help you, however, there are no answer choices.
