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1) $\sin \beta=\frac{8}{17}$\\
2) $4 \cdot \frac{\pi}{24}$\\
4) $x=77\cot 43.1999^\circ$\\
6) $x\tan 66^\circ=(1.1-x)\tan 76^\circ$\\
7) $90^\circ = 89^\circ 59'60''$\\
12) $(\frac{\pi}{2},1)+(\frac{\pi}{6},5)$\\
13) $360^\circ=2\pi \,\text{rad}$\\
15) $y=7\sin[2(x-\frac{\pi}{2})]$\\
16) $\theta=63^\circ$
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