6. (2 marks) Consider the four-bit adder-subtractor (with overflow detection) shown below. Adding two positive numbers together (A30 and B30) and get a negative number . Adding two negative numbers together (A31 and B31) and you get a positive number .In all other circumstances (adding two positives and getting a positive, adding two negatives Verify that the V output bit is correct for the following operations: (S3 1), the V output will be 1. (S3 = 0), the v output will be 1. and getting a negative, or adding a positive and a negative number), the V output will be 0. Bs A B2 A Bo Ao C3 C2 Co FA S3 S