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 couple of buses parked on the side of the street'. Find frequency of the letter 'b'

Answer: 1


Question: Sentence: 'a person does a trick on a ramp on a snowboard'. Find frequency of the letter 's'

Answer: 3


Question: Sentence: 'a little girl with a snack laughing on a bench'. Find frequency of the letter 'w'

Answer:
1