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Evaluate Expressions using the Commutative and Associative Properties

In the following exercises, evaluate each expression for the given value.

If $k=21,$ evaluate:

• ⓐ $\,\frac{4}{13}\left(\frac{13}{4}k\right)$
• ⓑ $\,\left(\frac{4}{13}\cdot \frac{13}{4}\right)k$