A system of folded membranes that functions as the internal delivery system of a cell

The model illustrates a process by which a substance is taken up by a cell

Suggest why placing wheels under a heavy box reduces the neccessary force required to push it along at a constant speed.

The picture shows a location in india that is very dry and arid. notice the tall mountains in the background; you can find high amounts of vegetation on the other side of the mountains. which statement is most likely true for this area?