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 dilapidated bench in a park under a tree'. Find frequency of the letter 'p'

Answer: 2


Question: Sentence: 'young boy flying kite in large field at outdoor event'. Find frequency of the letter 'y'

Answer: 3


Question: Sentence: 'an open umbrella near a stair way with a sky background'. Find frequency of the letter 'e'

Answer:
3