Where did the elements for water come from in the first place or in the very beginning?*
1) Fusion in stars
2) Solar winds
3) Volcanic eruptions
4) Photosynthesis

Because it's sugar that us the answer

It depends on the surface of the levels. the rougher the surface, the greater is the frictional force. for rougher surfaces, you would need to exert greater force to move the object. the concept is that, you must overcome the frictional force in order to bring the object into motion. this is the reason why we add lubricants to the joints so they could easily move. this answer was on

Leaves specifically the gas exchange between plants and the environment. while plants undergo photosynthesis, they also partake in cellular respiration. respiration is the process that happens in the leaves of plants.