Answer:
B) It was a major achievement when it was declared "separate but equal" was unconstitutional.
Explanation:
Prior to the Brown v. the Board of Education Supreme Court case in 1954, there was a a doctrine in American Constitution law known as "separate but equal". This doctrine allowed people to be segregated by race in public facilities such as schools, trains and bars, as long as the quality of service remained the same.
The Supreme Court in the Brown v. the Board of Education case, ruled that “separate educational facilities are inherently unequal.”
Therefore, the "separate but equal" doctrine which supported black and white students attending different public schools, was rendered unconstitutional.
The emancipation proclamation
The object must move with the speed of 
times to approximately seeing that it is contracted to exactly half of its actual length.
<h3>How is this calculated?</h3>
The length contraction experimented by the object as it approaches lightspeed, in meters per second, is described by Lorentz contraction formula:
Here, v is the current speed m/s
c is the speed of light in m/s
L' is the length of the object at rest in m
L is the length of the object at the current speed in m
Now we know that
and 
then,
Hence, r = 
Therefore, the answer is the object must travel at a speed of times the lightspeed to be contracted to one-half its proper length.
To know more about the Lorentz contraction formula, visit:
brainly.com/question/17407131
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A. They were trying to find a trade route to make trading easier, so they explored a whole lot more.
B. The Colombian Exchange contributed to the rise of slave trade because when they picked up goods, they just piled 100 or so slaves in the bottom deck. Once a few people had some, many others began to want them and supply and demand skyrocketed. It was easy because the slaves had a different skin color and spoke a different language. The Europeans did not see them as people.
