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 man serving himself pizza in a wooden booth'. Find frequency of the letter 'n'

Answer: 4

Question: Sentence: 'a bird on a tree is flapping its wings'. Find frequency of the letter 'o'

Answer: 1

Question: Sentence: 'a group of three women working on something at a kitchen'. Find frequency of the letter 'm'

Answer:
2