Only era can vary in length of time.Era means age,period which doesn't exactly define the time
Century=100 years
decade=10 years
millennium = 1000 years,
In the early 1900s, African Americans wanted to leave the south because of poor economic conditions (share cropping, etc) and racial discrimination. Slavery had just been abolished in 1865, so people hadn't quite accepted the idea of racial equality. It can be argued that we still haven't.
Based on the given image above, the correct answer would be the first option. Based on the political cartoon, the conclusion that can be made about Boss Tweed and the Democratic Party political machine known as Tammany Hall is this: <span>The substantial power held by Boss Tweed and Tammany Hall was achieved through political corruption. Hope this answer helps.</span>