This rule indicates that the United States economy has become increasingly dependent on?

chinese civil war took place over a long period of time between 1927 and 1950. the war was interrupted when japan invaded china in 1936 and by world war ii. the war was fought between the nationalist government of china, also called the kuomintang (kmt), and the communist party of china (cpc). 

the answer would be the third option, "no, ariel should have added 9^2 and 12^2 and compared that to 15^2."

this is found through the pythagorean theorem, which is a^2 + b^2 = c^2.

this is the correct way of solving the problem:

9^2 + 12^2 = 15^2

81 + 144 = 225

225 = 225