Answer:
C: Nitrogen
Explanation:
nitrogen is transparent to infrared light. the molecules are invisible because when you stretch one, it doesn't change the electric field.
Answer:
D. sulfur oxides from factories
Explanation:
This does not naturally occur, only if there is a factory. These other things happen on their own in nature but sulfur from factories relies on other factors down on earth.
The correct answer for the blank is: Surrounded by a moving border.
I hope that helped you! c:
I think it’s C but I could be wrong