The four faces of a right triangular pyramid are equilateral triangles whose edge measures 3 dm. Suppose the pyramid is hollow, resting on one of its faces at a horizontal surface (see attached figure) and that there is 2 dm3 of water inside. Determine the height that the liquid reaches inside the pyramid.
https://cdn.artofproblemsolving.com/attachments/0/7/6cd6e1077620371e56ed57d19fd3d05a58904e.png geometry3D geometrypyramid