Question

Put an H next to the items that describe Human Systems
Put a P next to the items that describe Physical Systems.
canals
faults
floods
bridges

Answer 1

Canals are man-made, meaning, they are Human Systems. 
Faults are natural, meaning, they are Physical Systems. 
Floods are not created by man, meaning, they are Physical Systems. 
Bridges are man-made, meaning, they are Human Systems. 

I hope this helps!