<span>B Experts today estimate 20,000-30,000 laborers worked on the pyramid at any one time.
This is the best option out of all the options. The statement should support the idea that many people were needed to build the pyramid. Options A and C do not really indicate the amount of people the were necessary to build the pyramid. B and D are the only ones that give numbers. Option D however is not correct because even though it says that the work crews needed to be divided into smaller groups, it doesn't give a true indication of the sheer amount of workers needed. Option B is a clear estimate of the tens of thousands of workers necessary to build a pyramid.
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The correct option is B.
The source of information, that would offer the most reliable fact-based information about the author is a book, that is written by the author himself. This type of source is called primary source. Information obtained from Wikipedia, movie and books published by other authors can only offer secondary information, which are not as reliable as information from primary source.
Answer:
Without trees, humans would not be able survive because the air would be unsuitable for breathing. If anything, people would have to develop gas masks that filter the little oxygen that would be left in the air. ... Anyway, trees take carbon from the atmosphere through photosynthesis in order to make energy
Explanation: