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2 problems match “multiset permutations”. Clear

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1. Almost palindromic letter arrangements ●●●○○ 50 ptsCall a string of letters $S$ an almost palindrome if $S$ and the reverse of $S$ differ in exactly two places. Find the number of ways to order the letters in $HMMTTHEMETEAM$ to get an almost palindrome.
2. Six-letter words using all letters ●●●○○ 50 ptsSix-letter "words" are formed using the letters A, B, C and D, with letters allowed to repeat. In how many of them does each letter appear at least once?