The illustration provided shows a river and four cities on that river. When the water from the river was sampled at location X, it was determined to be polluted with various chemicals. What would be the most likely source of this pollution?

A. City 1 & 2

B. City 4 only

C. City 3 & 4

D. City 3 only

i believe the answer is a or 1

a "theory" a suggestion that is not 100 % accurate, or a figure. some people say its a theory because they of all the passed theory's about one subject. it depends sometimes theory might be accurate and sometimes they are.

the answer is z.

the human body has five levels of organization. level 1: cells. cells are the basic units of life and form the first level of organization. cells in the human body have specific functions. examples include nerve cells, blood cells, liver cells, and so on.