Assignment 1 A four-bit adder-subtractor circuit is shown in the Figure below. The mode input M controls the operation. When M=0, the circuit is an adder, and when M=1, the circuit becomes a subtractor 8 4. 8. 4. 8 1 FA FA FA HA V The circuit hus the following values for mode input M and data inputs A and B. In each case, determine the values of the four SUM outputs (S0, S1, S2, S3) and the carry C. M A B 0 0111 (a) (b) 0 1 1000 1100 0101 0000 0110 1001 1000 1010 0001 (d) 1 1