I believe that it is D. All of the above.
<em>If this is incorrect, please, do tell me and I can fix my mistake. Thank you.</em>
Answer:
One of the physical characteristics about a gas is that it is not a solid and it is an invisible gas
Explanation:
12. One of the physical characteristics about a gas
<span>Although both macro algae and mangrove trees are multicellular and share many of the same structural features, macro algae are not true plants. Also, mangrove trees and marsh plants typically live in brackish water rather than salt water and are not completely submerged, as opposed to macro algae.</span>
B. specific - meaning it is only able to catalyze a reaction with a certain molecule
The answer is a. the troposphere
