The answer is C: A surfer rides back to the beach on his surf board.
All the others are examples of people doing stuff to the water, C is an example of the water moving something, in this case the water is moving a surfer and his surf board.
Homogeneous:
denoting a process involving substances in the same phase (solid, liquid, or gaseous).
Herogeneous:
of or denoting a process involving substances in different phases (solid, liquid, or gaseous).
1) CH2 (gas) + Br (solid) -> BrC (solid) + H2 (gas)
2) a) CH4 + Br2 -> CH3Br + HBr
2) b) methane + bromine is substitution because one hydrogen atom from methane is replaced by one bromine atom. addition reaction takes place when one molecule combines with another to form a larger molecule so therefore a molecule from X and bromine combine to form XBr.
