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 small doughnut held in a persons hand'. Find frequency of the letter 'n'

Answer: 4

Question: Sentence: 'a small wrinkley dog wearing a bow tie'. Find frequency of the letter 'e'

Answer: 3

Question: Sentence: 'there is a man sitting on a green bench'. Find frequency of the letter 't'

Answer:
3