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 in a black shirt prepares to catch a frisbee'. Find frequency of the letter 'f'

Answer: 1


Question: Sentence: 'two metal  benches on an empty train platform'. Find frequency of the letter 'n'

Answer: 4


Question: Sentence: 'a road sign indicating that to get on interstate 94 you need to take the next left'. Find frequency of the letter 'd'

Answer:
3