Light does not travel at a constant speed in a vacuum, compared to in air, because the light is being absorbed by atoms and molecules in the air. But light does travel at a constant speed in a vacuum.
So I agree with A
All that talk about moving forward is irrelevant (I think)
<em>Answer: </em>D
<em>Explanation:</em>
chemical formula of methane: CH4
electron configuration of C: 2,4
electron configuration of H: 1
there are 4 hydrogen atoms that donated 1 electron each to C
therefore it's D.
I think the answer is C but don’t quote me on that