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: 'small black bird with red on its head standing on a tree branch'. Find frequency of the letter 'b'

Answer: 3


Question: Sentence: 'a blue fire hydrant painted on the bottom of it'. Find frequency of the letter 'h'

Answer: 2


Question: Sentence: 'a small red bird is peeking through the window'. Find frequency of the letter 'n'

Answer:
2