it's the last one because it's depended on the rock layers
The answer is d I'm pretty sure because the second one and the first one don't make sense but I'm not 100 percent positive about it not being d ..... sorry if it's wrong.
Answer:
Exosphere
Explanation:
it is found at the end reaching outer space
I think it’s light
Have fun :)
Answer is: CH4 and NaCI hope this helps you
