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: 'people waiting on a train platform in a wooded area'. Find frequency of the letter 'p'

Answer: 3

Question: Sentence: 'a bunch of green bananas is hanging on a tree'. Find frequency of the letter 'n'

Answer: 7

Question: Sentence: 'traffic lights signaling to go on the empty street next to the gas station'. Find frequency of the letter 'n'

Answer:
5