What is the answer to number 7, 8, and 9?

number 7: Czar Nicholas II was the last czar, and Russia replaced him with a communist government.

number 8: The treaty of Versailles was the treaty that brought world war 1 to an end.

number 9: Woodrow Wilson came up with the idea of the league of Nations,  The League's goals included disarmament, preventing war through collective security, settling disputes between countries through negotiation diplomacy and improving global welfare.

zheng he was a chinese explorer who lead seven great voyages on behalf of the chinese emperor. his seven total voyages were diplomatic, military, and trading ventures, and lasted from 1405 – 1433. however, most historians agree their main purpose was to promote the glory of ming dynasty china.

explanation:

abraham lincoln  (february 12, 1809  – april 15, 1865) was an american statesman, politician, and lawyer who served as the 16th  president of the united states  from 1861 until  his assassination  in april 1865. lincoln led the nation through the  american civil war, its bloodiest war and its greatest moral, constitutional, and political crisis.[2][3]  he preserved the  union,  abolished slavery, strengthened the  federal government, and modernized  the u.s. economy.