Given four inputs: a, b, c & d, where (a, b) represents a 2-bit unsigned binary number X; and (c, d) represents a 2-bit unsigned binary number Y (i.e. both X and Y are in the range #0 to #3). The output is z, which is 1 whenever X > Y, and 0 otherwise (this circuit is part of a "2-bit comparator"). For instance, if a = 1, b = 0 (i.e. X = b10 => #2); c = 0, d = 1 (i.e. Y = b01 => #1); then z = 1, since b10 > b01

Just need truth table, and boolean expression (simplified) for these thumbs up.