Faces $$ABC^{}_{}$$ and $$BCD^{}_{}$$ of tetrahedron $$ABCD^{}_{}$$ meet at an angle of $$30^\circ$$. The area of face $$ABC^{}_{}$$ is $$120^{}_{}$$, the area of face $$BCD^{}_{}$$ is $$80^{}_{}$$, and $$BC=10^{}_{}$$. Find the volume of the tetrahedron.

(第一十届AIME1992 第7题)