By rename do you mean turn into an improper fraction?
if so, it is because without turning it into an improper fraction, you cannot subtract 3/4 from 1/4 because you would get a negative answer and that would be incorrect
High levels of dissolved oxygen
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B. In the twentieth century alone, the world population grew by more than 5 billion people.
C. Population grew slowly until the eighteenth century because death rates were higher.
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- Hannah ❤
