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 playing wii bowling in a modern library'. Find frequency of the letter 'o'

Answer: 3


Question: Sentence: 'a photo of a couple of people at a convention'. Find frequency of the letter 'v'

Answer: 1


Question: Sentence: 'pedestrian in stripe clothing standing on street corner'. Find frequency of the letter 's'

Answer:
4