We have squares ABCD and EFGH. Square ABCD has points with coordinates A=(1,1,−1), B=(1,−1,−1), C=(−1,−1,−1) and D=(−1,1,−1). Square EFGH has points with coordinates E=(2,0,1), F=(0,−2,1), G=(−2,0,1), and H=(0,2,1). Consider the solid formed by joining point A to H and E, point B to E and F, point C to F and G, and point D to G and H. Compute the volume of this solid.