Which force helps drive erosion of sediments by a mountain stream?

the options are-
A) gravity
B) magnetism
C) chemical bonds
D) plate tectonics

(also i don’t know what subject this goes into)

Which type of bacterial reproduction is depicted in the diagram?

What is the membrane that sheath of schwann cell containing cytoplasm and nucleus that encloses myelin

The scales shown in the introduction measure mass, or the amount of matter in a particular object. the scientific law of conservation of mass states that matter cannot be created or destroyed during a chemical reaction, but it can change from one form to another. did the simulation support this scientific law? explain why or why not.