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 man with headphones on is hunched over a sink while being recorded'. Find frequency of the letter 'd'

Answer: 4


Question: Sentence: 'a large bathroom with marble floor, counter, and bath'. Find frequency of the letter 'f'

Answer: 1


Question: Sentence: 'a fire hydrant sits in the middle of a grass patch'. Find frequency of the letter 'r'

Answer:
3