.
            I will answer  ## 3, 4 and 5 only.
3.  The sample space in this case is the set  { 0, 1, 2, 3, 4 , 5 },  consisting of six integer numbers from 0 to 5 inclusive.
    It is the list of all possible outcomes, according to the definition of a SAMPLE SPACE.
4.  The sample space in this case is the same set as in  #3.
5.  The sample space in this case is the set of all 3-letter words written in the 2-letter alphabet  (H,T).
    In other words, this set is
        HHH
        HHT
        HTH        
        HTT
        THH
        THT
        TTH        
        TTT
    In all, there are  
 = 8 elements in this sample space.