In this task, you need to count the number of times the given letter appears in the given sentence.
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Question: Sentence: 'a couple of men sitting next to each other under an umbrella'. Find frequency of the letter 'n'

Answer: 5

Question: Sentence: 'a plane with smoke coming from the tips of both wings'. Find frequency of the letter 'c'

Answer: 1

Question: Sentence: 'a large blue truck drives down the road'. Find frequency of the letter 'a'

Answer:
3