We toss a coin until either Heads appear for the first time or we have five tosses which all result in Tails. Give a suitable sample space for this experiment, and then write explicitly (i.e. by listing their elements) each of the following events:

A: the experiment terminates at the third toss of the coin;

B: the experiment terminates after the third toss of the coin;

C: the experiment terminates before the fourth toss of the coin;

D: the experiment terminates with the appearance of H (Heads).
Which, if any, of the events A, B,C,D are elementary events in the sample space that you have considered?