<span>(I am in middle shcool but I will try to help) Inventions such as the McCormick reaper and the steel blow made farming more efficient but meant that fewer laborers were needed to work the land. As more and more farms merged, many rural people moved to cities to find whatever work they could.(hope this helps)
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I believe the answer is: double-blind experiment
In double blind experiments, the subjects that receive the treatment is remained unknown by both the researchers and the subjects until the experiment is finished. The main purpose of double-blind experiment it eliminate the bias of perception that might exist among researchers.
False or truth what question
