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: 'a police officer who is riding on a horse'. Find frequency of the letter 'p'

Answer: 1


Question: Sentence: 'a biplane flying low over a planted field'. Find frequency of the letter 'w'

Answer:
1