22. In order to survive in its environment, a single-celled organism uses a contractile vacuole to remove excess water that diffuses into its cell. Another
species, a hydra, also excretes excess water. Both processes involve the use of
energy. Which type of transport would be used by these organism?

The answer is c the potato slice shriveled because water moved out of the slice into the salt solution

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

That is false even though water expands when frozen nothing changes at all 

Iam to type 39 active barriers virus a nonucleoside thocarbanlide 22 ficeney