The sample space is the complete list of every possible outcome of an experiment — the foundation everything else in probability builds on.
1-A 2-A 3-A 4-A | 5 sample space 6 8 7 = S = {1,2,3,4} 8 = 8 9 = {HHH,HHT,HTH,HTT,THH,THT,TTH,TTT} | 10 = 36