The answer to your question is B. However the troops were eventually withdrawn from Vietnam due to disagreements from the American people.
Automation is when things move or do things by themselves. a engine that runs by itself.
The answer is D. <span> invention of the first steel tools
Actually, this very topic is still a hot debate among scientists because the shift happens on different reasons in each region of the world.
But one thing they have in common is that Steel tools give the member of early societies the capabilities to rake uplands and cutting up crops that really useful in farming and herding.</span>
The primary purpose of the Iroquois League was "<span>D. to bring independent nations together for mutual defense and common concerns", since European invaders had begun to seek more territory. </span>
