Consider the following 4-bit ALU, and answer the questions below. (a) What does the term 'ALU' stand for? A Opcode F F Fo 0 0 0 1 21 do o 0 0 1 (1) (b) Given the 4-bit ALU shown above, explain how each of the four status bits in the status register S: N - negative, Z - zero, V - overflow and C - carry are generated. You have access to the individual bits of A, B, Y, F and the carry-in and carry-out bits of the individual adders. 1 ALU (4) (c) Design an arithmetic circuit for the ALU above, which has a 3-bit instruction set. The opcodes in the instruction set are provided in the table below. Only design the system for the 1-bit case. You have the following components available to you: 1-bit full adders, multi-bit wide multiplexors, AND, OR, NOT, NOR, NAND and XOR gates, decoders etc. TTOOTT 0 0 Ono-o- 1 1 0 1 1 1 0 1 1 1 0 4 B 1 4 Operation F s A+B A-B A+B B-A A-1 A+1 +1