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6. \qquad $\sqrt{100,000}$
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7. \qquad $\sqrt{17}/17 = 17/\sqrt{17}$
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8. \qquad $\sqrt{.5}$
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9. \qquad $\sqrt{2.5^2 + 3.4^2} = 2.5 + 3.4$
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14. \qquad \fbox{\rule [-4pt]{0pt}{16pt}\ $\bullet$\ }
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21. \qquad$$\int_{-1}^2 x^3\,dx $$
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23. \qquad $(x_1 -c)^2 + (x_2 -c)^2 + (x_3 -c)^2 + (x_4 -c)^2 $ 
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