Let A,B and C are three arbitrary events.Find the expression for the events noted below,in the context of A,B

Question

and C.
(i) Only A occurs (ii) Both A and B,but not C occurs (iii) All the three events occurs
(iv) At least one occur

Answer 1

(i) Only A occurs: A and not (B or C)
(ii) Both A and B, but not C occurs: A and B and not C
(iii) All three events occur: A and B and C
(iv) At least one occurs: A or B or C