In Quadrant II, cosine is negative, and since $\sin^2{0} + \cos^2{0} = 1$, we have:
$\cos{0} = -\sqrt{1 - \sin^2{0}} = -\sqrt{1 - 0^2} = -1$
Now, we can use the double angle formulas to find the exact values of $\sin{20}$, $\cos{20}$, and $\tan{20}$:
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