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 young boy wearing black and holding a skateboard on the sidewalk'. Find frequency of the letter 'n'

Answer: 5


Question: Sentence: 'many different species of sheep in display at a museum'. Find frequency of the letter 'h'

Answer: 1


Question: Sentence: 'there is a toilet brush and holder in this very modern bathroom'. Find frequency of the letter 'r'

Answer:
6