Question 13: The set A of natural numbers not less than 1 and not greater than 5 is written in which of the following forms?

The set A includes the natural numbers x such that x is not less than 1 and not greater than 5, ie x is greater than or equal to 1 and x is less than or equal to 5, so we have:

\(A = \left\{ {x \in\mathbb{N} |1 \le x \le 5} \right\}\)

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