Which two eras ended with mass extinctions?
its paleozoic and mesozoic right? ?

after world war ii, the united states and the soviet union were the major economic, military, and political powers. the world was bilateral multipolar bipolar unilateral

after world war ii, the united states and the soviet union were the major economic, military, and political powers. the world was bipolar.  

the great leap forward, mao zedong's plan to increase china's agricultural and industrial production, was an overwhelming success. true false

the great leap forward, mao zedong's plan to increase china's agricultural and industrial production, was an overwhelming success. true.

explanation:

in 1989, tiananmen square in beijing was the site of china’s main industries. china’s government headquarters. -pro-democracy demonstrations. (second choice)

ok

explanation: