number 1 and 2 please..

Give the detail design procedures and your explanations. 1. (a) A half adder is a circuit that adds two bits to give a sum and a carry. Give the truth table for a half adder, and design the circuit using only two gates. (5%) (b) Then design a circuit which will find the 2's complement of a 4-bit binary number. using four half adders and any additional gates. (10%) (c) Design a four bit binary adder by using the half adder designed in (a). (5%) (d) Using the circuit designed in (c) to de sign a circuit which will find the 10's complement of a BCD digit. (10%) 2. Design an excess-3 code converter to drive a seven-segment display. Assume that only input combinations representing the digits 0 through 9 can occur as inputs. Design your circuit using only NAND gates and inverters. Try to minimize the number of gates and inverters required. Any solution with 16 or fewer gates and inverters is acceptable. (10%)