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

Answer: 4


Question: Sentence: 'a coffee cup is sitting on a desk in front of a keyboard'. Find frequency of the letter 'y'

Answer:
1