Write the indicated event in set notation.When four coins are tossed, the first three tosses come up the same.[Hint: when four coins are tossed, the following 16 outcomes are possible:HHHH HHHT HHTH HHTTHTHH HTHT HTTH HTTTTHHH THHT THTH THTTTTHH TTHT TTTH TTTT ]a. (HHH, TTT) b. (HHHT, TTTH) c. (HHHT, TTTH, HTTT, THHH) d. (HHHH, HHHT, TTTH, TTTT)