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: 'the ingredients are ready on the wooden table'. Find frequency of the letter 'w'

Answer: 1


Question: Sentence: 'a black train approaching a train station stop'. Find frequency of the letter 'c'

Answer:
2