<u>Answer:</u>
<em>D. Even though slaves were still considered property, some slaves had kind masters
</em>
<u>Explanation:</u>
According to Calhoun’s argument, the blacks were much better while serving as slaves in America than they were when they were free. This was because of racial inferiority. Since that is inferior, they are given better from the whites
Calhoun also argues that the slaves were better than free workers. This was, therefore, a common argument in the regions of the south. The slaves were better because they were treated well by their masters since the master aimed to take care of their investments.
A radioactive element with a half-life of 1,000 years, and starting mass of 20 grams, will need 2,000 years to decrease to 5 grams.
Explanation:
The radioactive elements all have a specific half-life. Each element's half-life is well known, and they are used by scientists of numerous fields as they are excellent for determining the age of a particular item, be it or organic or non-organic nature. In this case, we have a radioactive element with a half-life of 1,000 years, and starting mass of 20 grams.
The half-life basically means that half of the mass of an element is lost during a particular period of time. For the element in question we need to find out how much time will be needed for it to decrease to 5 grams. In order to get to the result, we just need to add 1,000 years on every decrease of half of the mass:
20/2 = 10
10/2 = 5
So in 1,000 years, the element in question will decrease to 10 grams, and in further 1,000 years (2,000 cumulatively) it will decrease to 5 grams.
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Hydrogen is used by plants which combine it with carbon during the photosynthesis process and release oxygen into the atmosphere which is used by all living beings.
Answer:
1: A 2: 1,3
Explanation:
Alfred wegner had gained an idea from this and later turned it to a theory
And it's one and three because he had used mutiple different fossils and species from different continents that were the same thing in two different places and shown the glacier marks on seperate continents not naturally having glaciers.
