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 dog sits in the rear window of a car'. Find frequency of the letter 'm'

Answer: 1


Question: Sentence: 'this marketplace has a lot of fresh fruit and vegetables'. Find frequency of the letter 'v'

Answer: 1


Question: Sentence: 'a picture of a person that is buy some food'. Find frequency of the letter 'a'

Answer:
3