Alice, Bob, Charlie, and David are planning to attend a workshop, but there are only 3 available seats. Additionally, specific conditions apply: i. At most two of them can attend. ii. If Alice attends, Bob will also attend. iii. Charlie will only attend if David attends. iv. Bob cannot attend because he has a conflicting meeting. Let's denote the propositional variables: A: Alice will attend. B: Bob will attend. C: Charlie will attend. D: David will attend. a- Using these four literals (A, B, C, D), write the propositional logic formulas corresponding to this text (for each i, ii, iii and iv) b- Find (through a formal proof) who will attend the meeting.