Recall that A NOR B equals 1 if and only if both inputs are 0. If at least one input is 1, then A NOR B equals 0. A B out B A-Do-out A B A NOR B 00 1 0 1 0 1 0 0 1 1 0 Prove that NOR is also a universal gate. To do this, express each of P, PV Q, PAQ, and P Q solely as a combination of NOR gates. Clearly justify your answers.