Answer
$b \approx 58.2 km$
$\angle B = 58^{\circ} 20'$
$c \approx 68.4 km$
Work Step by Step
1. $\angle B = 90^{\circ} -31^{\circ} 40' = 58^{\circ}20'$
2. $\tan 31^{\circ} 40' = \frac{35.9}{b}$
$b= 35.9 \tan 31^{\circ} 40'\approx 58.2 km$
3.$\sin 31^{\circ} 40' =\frac{35.9}{c}$
$c = 35.9 \sin 31^{\circ} 40' \approx 68.4km$
