How did the four river valley civilizations differ? ( give me like 3 or 4 reasons) : )

answer; /// i believe that the correct answer is (d)the huang he river valley;

1.3x - 2 - (3.3x + 5) = 2x + 1

1.3x - 2 - 3.3x - 5 = 2x + 1

-2x - 7 = 2x + 1

-7 = 4x + 1

-8 = 4x

x = -2

the correct answer is “opportunity cost”. opportunity cost is what a company misses out because it decided in one option over another one. in this case, the company decided to invest in building a factory so it gave up another possible benefit or profit in order to achieve success with the factory.  

trade-off is not the correct answer since it is a situation in which you accept losing something in return for benefits in other areas.

and finally, consequence is a general term used to accept what it comes when you make a decision. it can be a positive or negative consequence depending if the decision you took was the correct one.