Yes, because the envelope can be a important document- so therefore it can be considered "confidential".
Answer:
Troposphere, stratosphere, mesosphere, thermosphere
this is the layers from space into earth
Answer:
you could calculate the speed of a snail or a cheetah by measuring a distance and measuring the time it takes them to get there. direction would be considered if you were finding velocity.
Explanation:
The structure of the lipid bilayer allows small, uncharged substances such as oxygen and carbon dioxide, and hydrophobic molecules such as lipids, to pass through the cell membrane, down their concentration gradient, by simple diffusion.
