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 white police vehicle parked on a paved street'. Find frequency of the letter 'a'

Answer: 4


Question: Sentence: 'a toilet of some sort near a sink of some sort'. Find frequency of the letter 'o'

Answer: 7


Question: Sentence: 'a white cow in a field of brown grass and some trees'. Find frequency of the letter 'f'

Answer:
2