4.3) (a) 3-bit binary adder, (b) 4-bit binary subtractor
6.1) (a) 4-bit shift register, (b) 3-bit Johnson counter
3.2) F = (x + y)'(x' + y')
2.3) (a) 110101, (b) 101101, (c) 111101, (d) 100101
1.3) (a) 10, (b) 11, (c) 101, (d) 110
2.1) (a) 11010, (b) 10100, (c) 11110, (d) 10010
5.3) (a) Moore machine, (b) Mealy machine