A bar graph titled San Francisco's Population, 1860 to 1920. The x-axis is labeled in years from 1860 to 1920 by each decade. The y-axis is labeled Population from 50,000 to 550,000 by 100,000. 1860 is less than 50,000. 1870 is 150,000.
By about how much did San Francisco’s population increase between 1860 and 1870?
by 100,000 people
by 140,000 people
by 210,000 people
by 70,000 people