I think it is A. but then you can also produce your own energy
It is difficult for astronomers to find object like planets and asteroids because it takes a lot of time to verify the objects locations and what surrounds a certain object in order to prove and be precise of its location
F = G*((m sub 1*m sub 2)/r^2)
Which of the following are characteristics of noble gases?

✅
- An inert gas is one that does not undergo chemical reactions. The noble gases have complete outer shells, so they have no tendency to lose, gain, or share electrons. This is why they are said to be inert.
✅
- Noble gases are the least reactive of all elements. This is because they already have the desired eight total 's' and 'p' electrons in their outermost (highest) energy level.
