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

Answer: 1


Question: Sentence: 'a flock of sheep grazing in a park'. Find frequency of the letter 'f'

Answer: 2


Question: Sentence: 'a fighter plane is taxiing down a runway'. Find frequency of the letter 'a'

Answer:
5