How many 8 digit numbers are there, such that they are divisible by 9 and all of the digits are distinct?

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How many ways can you arrange 5 identical Rooks on a 6 by 10 Chessboard in such a way that none of the rooks attack each other ?

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Consider all the 7-digit numbers containing each of the digits 1, 2, 3, 4, 5, 6, 7 exactly once and that are not divisible by 5. They are arranged in a list in increasing order. Find the 2000th number in this list.