Answer:
Abraham Lincoln is elected the 16th president of the United States over a deeply divided Democratic Party, becoming the first Republican to win the presidency. Lincoln received only 40 percent of the popular vote but handily defeated the three other candidates: Southern Democrat John C. Breckinridge, Constitutional Union candidate John Bell, and Northern Democrat Stephen Douglas, a U.S. senator for Illinois
Explanation:
An increase in efficiency
After the Qin Dynasty collapsed in 207 BC after four years of civil war, Liu Bang established the Western Han Dynasty
