Anaphylaxis is a severe, potentially life-threatening allergic reaction. It can occur within seconds or minutes of exposure to something you're allergic to, such as peanuts or bee stings.
Answer:
The Sun
Explanation:
it is essential to doing photosynthesis
1. B
2. B
3. C
4. C
5. D
6. C
7. C
8. D
9. C
Pressure decreases with increasing altitude.