Answer
28.2 mi
Work Step by Step
Step 1. Use the figure given in the Exercise, the angle between the boat paths is $180-50-70=60^{\circ}$, the distance of boat1 traveled is $30mi$ and the distance of boat2 traveled is $26mi$
Step 2. Use the Law of Cosines, the distance between the two boats after 1h is $d^2=30^2+26^2-2\times30\times26cos60^{\circ}=796$ which gives $d\approx28.2mi$
