4.1 Universal Gates (10 marks) A NAND gate or a NOR gate is a universal logic gate, because it can be used to construct all other logic gates. What is the minimum number of two input NAND gates required to implement the following Boolean expression F(X, Y, Z, W) = (X+) . (Z + W), where X, Y, Z and W are inputs? Explain your reasoning. One you have figured out the minimum number of required NAND gates, draw the circuit in Logisim using only NAND gates and test it. The TAs should be able to change the logical values of the inputs while obtaining the correct output