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 tower with some bright lights and clocks on it'. Find frequency of the letter 'h'

Answer: 3


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

Answer: 5


Question: Sentence: 'a man sitting in front of a double decker bus'. Find frequency of the letter 'r'

Answer:
2