Answer:
City 1 and City 2
Step-by-step explanation:
The water is moving down stream, moving from City 1-2-3-4 in that order.
if water was taken a the X mark, the pollutants would have to have come from the cities above where the sample was taken.
Hope this helps!
Answer:
x=4 y=0
Step-by-step explanation:
7(4)-5(0)=28
28-0=28
28=28