Q1 20 points User IDs on an old computer system consist of 4

Q.1 (20 points) User IDs on an old computer system consist of 4 letter sequences from the first 8 letters of the English alphabet: a, b, c, d, e, f,g,h. Note that the same letter can he used any number of times in the 4 letter sequence. When a new user first registers. an ID is randomly generated (all outcomes equally likely) with the only condition that it is different from the Ins of all previously registered users. a) How many different IDs are possible for the first registered user? b) What is the probability that the ID for the first registered user will start with the letter c and end with the letter g? c) How many different IDs are possible for the second registered user? d) Jack, Kate and Sawyer are the only three users of this system. In how many different passible ways can they be assigned IDs? For instance, one possible way is: Jack\'s ID = ahhb, Kale\'s ID a=beda. Sawyer\'s ID =bhhh

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