Air pollution increased dramatically with the invention of

Which factor has played the most important role in changing the way history is studied over time?

In ohio in 1872, the cleveland massacre was a violent labor dispute at standard oil refineries in cleveland. a takeover by standard oil of the refineries in cleveland. an attempt to stop standard oil from becoming a monopoly. a failed attempt by standard oil to take over other refineries.

What are the expressed and implied powers of the president