(a) Find the octal expansion of the integer 4812. (b)(i) How many ways are there to arrange the letters of the word DISCREAT? (ii) How many of these ways (in part (i)) start with D and end with T? (iii) How many of these ways (in part (i)) start or end with the letter D?

[3+(1+1+1)=6 marks]

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