2 (2 marks) A full binary subtractor circuit has three inputs x, y, Bin, and two outputs D and Bout. The circuit performs the operation x- y - Bin. The output Bout equals 0 if no borrow is required to perform the subtraction, and 1 if a borrow is required. a) (1 mark) Find the truth table and simplify the equations for D and Bout using K-maps. b) (1 mark) Draw a block diagram showing how four full subtractors can be used to implement a 4-bit subtraction