Suppose that a coin is tossed three times,Then the sample space contains the following eight possile outcomes s1 ,......s8 , s1 :HHH, s2 :THH, s3 :HTH, s4 :HHT s5 :HTT, s6 :THT, s7 :TTH, s8 :TTT Give the following events. A: at t least two head is obtained B: get a head on the second toss C: no heads are obtained Questions 1: A={ ________ }, B={ ________ }, C={ __________ } Questions 2: ={ __________ }; B A={ ______ } (C B)={ }