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 tennis player that is running to get the tennis ball'. Find frequency of the letter 't'

Answer: 7


Question: Sentence: 'a gray colored pigeon that is perched on a railing outside of a building, with other buildings in the background'. Find frequency of the letter 'e'

Answer: 7


Question: Sentence: 'two girls and a boy playing on a tennis court'. Find frequency of the letter 'p'

Answer:
1