It would be "d. eight-hour days" that was not a problem faced by workers in nineteenth century mills or mines, since legislation advocating for strict working hours did not come about until the Progressive Era.
During the 1800s and 1900s, the advancement of technology changes the way we do our daily activity
The same thing happen in our current period. The development of technologies and the advance of internet allow us to do a lot of remote jobs that we're unable to do before
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It was the My Lai Massacre. This was when 24 U.S. soldiers
killed more than 500 civilians including men, women and children. It was said to be most shocking incident of
the war and generated international outrage due to the brutality of the
killings committed there.