What were the political and economic cause of the American revolution

Explanation:

Some of the main economic causes of the American Revolution are mainly due to Britain's unfair actions regarding trade, social order and incrementation of taxes. ... After 1765, when King George III increased taxes in the American colonies to pay for the British debts of the Seven Years War

the mongolian invasion of china and central asia resulted in a disruption of the silk road as the chinese garrisons lost support from the chinese kingdoms which fell under the mongols. however, as the mongols established a formal dynasty in china, the successors of genghis khan restored the garrisons along the silk road allowing the safe travel caravans again.

the graph shows the spread of railways in the 1800s.

based on the graph, the conclusion that can be drawn about germany is answer d)   by 1880, germany had more rail lines than great britain and russia.