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 row of vintage cars in a grassy field'. Find frequency of the letter 'v'

Answer: 1

Question: Sentence: 'two laptop computers sitting on top of a white table'. Find frequency of the letter 'f'

Answer: 1

Question: Sentence: 'a white cat sits on a cat tree while a black cat sits on a chair and both cats look out of a window'. Find frequency of the letter 'c'

Answer:
6