suppose that a friend tells you that square root of 13 almost equal to 5 7

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  1. Suppose that a friend tells you that square root of 13 almost equal to 5.7 . Without a calculator,how can you convince your friend that he or she must have made an error?
  2. Explain why cube root of negative 64 end root is a real number, but square root of negative 64 end rootis not.