Science
What part of all organisms Is involved in the exchanging of gases

Gas exchange occurs in microscopic dead-end air-filled sacs called alveoli, where a very thin membrane (called the blood-air barrier) separates the blood in the alveolar capillaries (in the walls of the alveoli) from the alveolar air in the sacs.

Explanation:

1. they vary with a higher number because boiling is way hotter than melting