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1. (10 Points) Consider a game in which words are formed using the English alphabet (all 26, lowercase letters). Of course, some words are meaningful (such as "cat"), while some "words" mean nothing (such as "cta"). For the sake of this problem, we will consider any combination of letters to constitute a word. a.) How many 3-letter words can be formed, assuming letters may be repeated? b.) How many 3-letter words can be formed, assuming letters may not be repeated? c.) Suppose you are to form a phrase consisting of 2 words, The first word must have 4 letters and the second word must have 5 letters. Assuming letters can be repeated, how many of these phrases can you form? d.) Suppose you are trying to construct 10-letter words. You need to use 4 a's, 3 b's, 1 d, and 2 f's. How many 10-letter words can you form from only these 4 distinct letters