How did the Mongol Empire interact with other nations during peacetime? a The Mongols invited other nations to join their empire.
b The Mongols worked with border nations to control their borders.
c The Mongols formed trade and diplomatic ties with many nations.
d The Mongols created alliances to prevent other countries from attacking.

answer:   c.

it was not against the chinese government.

explanation:

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.