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 woman swinging a tennis racquet towards a tennis ball'. Find frequency of the letter 'e'

Answer: 3

Question: Sentence: 'there is no image here to provide a caption for'. Find frequency of the letter 'o'

Answer: 5

Question: Sentence: 'a bear walking in a grassy open field'. Find frequency of the letter 'p'

Answer:
1