I would appreciate any help.

4. (20 pts.) The NAND operator, denoted by I, is defined by the following truth table: PPO TTIF FTT F FT Table 1: Truth Table for NAND (a) Prove or disprove the following statements: (b) Find a compound expression S, using only NAND operators, which is logically equivalent to P V Q. Show that S is indeed equivalent to P V