The election of 1860 is your answer. When the south got word of Lincoln’s election a few states started seceding within days. This led to the soon start of the war.
President Richard Nixon believed that North Vietnam was transporting troops and supplies through neighboring Cambodia into South Vietnam.
The industrial revolution was a period of time from the 1700 to the mid 1800 where new ideas and methods greatly improved.
Fireside chats were effective during the war because if gave up where the enemy was. It helped our soldiers find them and kill them quicker, than it would of if there was no such thing as fireside chats. The other thing it was good for was keeping the public informed. If the public wasn't informed, then there was a greater chance of more areas being obliterated during the war from not knoeing the enemy was getting ready to strike.
Hope this helps.
Answer:
B. a group of British colonies
Explanation: