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A contest consists of finding all code words that can be formed from the letters in the word "alpha".Assume that the letter "a" can be used twice but the others at most once:
a)How many five-letter words can be formed?
b)How many two-letter words can be formed?
with two letter words can be formed is 13
c)How many words can be formed?
5 letter words=60 4 letter words=60 3 letter words=33 2 letter words=13 1 letter words=4 so,60+60+33+13+4=170
Could you please check t for me?