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 group of tennis players on a tennis court'. Find frequency of the letter 'o'

Answer: 4


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

Answer: 3


Question: Sentence: 'a scene at night; a plane alone on a runway with lit-up city buildings on the horizon'. Find frequency of the letter 'w'

Answer:
2