To help predict eruptions from the volcano Mauna Loa on the island of Hawaii, scientists keep track of the volcano's movement by using a "super triangle" with vertices on the three volcanoes shown on the map at the right. (For example, in one year, Mauna Loa moved 6 in., a result of increasing internal pressure. / Refer to the map to work Exercises 71 and 72 .
$$\begin{array}{l}
A B=22.47928 \mathrm{mi}, A C=28.14276 \mathrm{mi} \\
A=58.56989^{\circ} ; \quad \text { find } B C
\end{array}$$
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