Assume x, y are Boolean variables, x(l + y) = x a) true b) false Which of the following is NOT a Boolean function? Given x, y, z are Boolean variables a) x AND y b) x OR y AND z c) NOT x d) x AND 2 Which of the following about truth table is NOT true? a) A visual representation of a Boolean function. b) A truth table only lists true cases for a Boolean function. c) Input variables to the left, and an output the right d) All possible input values (combinations) are listed. How many possible Boolean functions are there for two Boolean variables? a) 16 b) 32 c) 8 d) 4 Which of the following can be the sum of one-bit binary adder ? a) AND gate b) OR gate c) X-OR gate d) NAND gate What is the last stage of a SOP (sum-of-product) logic circuit? a) AND b) OR c) NOT d) NOR