Let A = a3a2a1ao and B = b3b2b1b0 be 4-bit 2's complement numbers. Shown below is the structure of an arithmetic unit AU), consisting of four 1 bit Full Adders FAs four copies of a circuit N and as shown. a2 b2 a3 b3 al bl a0b0 k1 ko k1 ko k1 kO k1 k0 b2" al* b1* ao* bo* a3* b3* C4 C2 Co FA FA FA FA S3 s2 S0 As specified in the table below, the AU will compute an arithmetic function, depending on the values of control signals k1 and ko k1 ko Function 0 0 2A+1 0 1 A-B 10 A-1 1 1-28-2 1. Express a and b* in minimal SOP form. Use K-maps to show your work. 2. Write a Boolean expression for co as a function of k1 and ko- Let A = a3a2a1ao and B = b3b2b1b0 be 4-bit 2's complement numbers. Shown below is the structure of an arithmetic unit AU), consisting of four 1 bit Full Adders FAs four copies of a circuit N and as shown. a2 b2 a3 b3 al bl a0b0 k1 ko k1 ko k1 kO k1 k0 b2" al* b1* ao* bo* a3* b3* C4 C2 Co FA FA FA FA S3 s2 S0 As specified in the table below, the AU will compute an arithmetic function, depending on the values of control signals k1 and ko k1 ko Function 0 0 2A+1 0 1 A-B 10 A-1 1 1-28-2 1. Express a and b* in minimal SOP form. Use K-maps to show your work. 2. Write a Boolean expression for co as a function of k1 and ko