Consider the two-by-four grid in Fig. 11.34. Assign the partial Gray code A = {00, 01, 11} to the three horizontal levels: top (00), middle (01), and bottom (11). Now assign the partial Gray code B = {000, 001, 011, 010, 110} to the five vertical levels: left, or first (000), second (001), third (011), fourth (010), and right, or fifth (110). Use the elements of A X B to label the 15 processors of this grid; for example, p1 is labeled (00,000), p2 is labeled (00, 001), p8 is labeled (01, 01l), p14 is labeled (11, 010), and p15 is labeled (11, 110). Show that the two-by-four grid is isomorphic to a subgraph of the hypercube Q5. (Thus we can consider the two-by-four grid to be embedded in the hypercube Q5.)