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 black bear sitting in the grass taking a rest'. Find frequency of the letter 'a'

Answer: 6


Question: Sentence: 'the street sign is next to a curved road'. Find frequency of the letter 's'

Answer: 3


Question: Sentence: 'a bathroom with a toilet, bathtub, and towel'. Find frequency of the letter 'h'

Answer:
3