Question 1152711
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I will answer (a) only.


<pre>
    (a)  The sample space is the set of all sequences of integer numbers  { {{{i[1]}}}, {{{i[2]}}}, {{{i[3]}}}, . . . , {{{i[n]}}}, 6 },
         that ending by 6.



         So, in these sequences, the integers {{{i[k]}}} are all between 1 an 5, inclusive, and 6 is the first and the only number "6" 
         in such sequences.
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