<span>The construction of the Berlin wall had shocked the western world, no one expected they would build a wall to isolate West Berlin. In response of the Berlin wall, U.S President John F. Kennedy had indicated that the western will not take any military action as long as they could remain the right and the free use of the transit in West Berlin. On July 25, President John F. Kennedy gave a speech to challenge soviet oppression and offer hope to the people that lived in the divided city. </span>
620,000 soldiers died from combat, accident, starvation, and disease during the Civil War.
The correct answer is B. They were able to find the orbit of a comet and predict the year of its return.
Edmond Halley was a British astronomer, geophysicist, mathematician, meteorologist, and physicist. Alexis Clairaut was a French astronomer, geophysicist, mathematician.
They were friends with Isaac Newton that before, had built a new theory of universal gravitation.
With this new theory, Newton calculated the orbit of the Great Comet of 1680. Later, Halley used Newton’s theory to calculate the orbits of several comets - even some that were in ancient records -. The thing is: Halley noticed that some comets had similar orbits, which led him to suggest that some comets may be periodic and that they may be moving along very elongated ellipses. This way he forecasted the comets return in a period of 76 years.
Since then, the comet has carried Halley’s name.
The main way in which the purchase of the Louisiana Territory and western expansion contributed to increased sectionalism in the United States is that each new potential state that was to be entered into the Union had to determine whether it was going to be "slave" or "free"--meaning that it further divided the North and South over the issue of slavery, and eventually led to the Civil War.
