. Evaluate, correct to 4 decimal places:
(a) cotangent $17.49^{\circ}$
(b) cotangent $163^{\circ} 52^{\prime}$
(a) $\cot 17.49^{\circ}=\frac{1}{\tan 17.49^{\circ}}=3.1735$
(b) $\cot 163^{\circ} 52^{\prime}=\frac{1}{\tan 163^{\circ} 52^{\prime}}=\frac{1}{\tan 163 \frac{52^{\circ}}{60}}$ $=-3.4570$