Answer:
China represents 20% of the people on Earth.
Serbia supplied the rebels with weapons so that they could kill the archduke. Austria-Hungary declared war on Serbia. Russia entered to defend Serbia because they both had large Slavic populations. Germany entered to defend Austria-Hungary. Alliances drew other countries in until it was a world war.
<span>The Self Strengthening Movement was a 19th century push to modernise China, particularly in the fields of industry and defense. </span>
Slavery for sure. I believe the second one is economic differences between the North and the South.
The answer is D. It provided a source of transportation for goods and people
