3. How many functions of one variable are there? How many functions of two variables are there? How many functions of n variable are there? 4. How many switching functions is a one-variable multiplexer capable of realizing? How many switching functions is a two-variable multiplexer capable of realizing? How many switching functions is a n-variable multiplexer capable of realizing? 5. Use a one-variable multiplexer to realize a NOT function (a NOT gate) with input A and output Z (Z = !A). Indicate the input i0 and il, the selector line, and the output for this MUX. i0: il: Selector line: Output: 6. Use a one-variable multiplexer to realize an XOR function (Z = A XOR B). If the selector line is A. indicate the input i0, and il and the output for this MUX. i0: il: Z