What does historical circumstances mean?

Supporters of using the atomic bomb at the end of world war ii believed that a japan might win the war if the bomb was not used. b americans were tired of war and the us should end it quickly. c russia was developing a bomb and the us needed to use it first. d japan was developing a bomb and the us needed to use it first.

The persian empire finally fell to the armies of

Which of the following are details about the compromise of 1877? election results in a couple of states were in dispute and too close to call. samuel tilden would be given the win in exchange for the removal of federal troops. the presidential election was close between rutherford hayes and ulysses grant. it was agreed troops would leave the south in exchange for a hayes victory.