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 yellow fire hydrant in the forefront of a roadway'. Find frequency of the letter 'r'

Answer: 5


Question: Sentence: 'two people holding their skies in a snowy resort'. Find frequency of the letter 'n'

Answer: 3


Question: Sentence: 'an old truck is at the bottom of a small hill'. Find frequency of the letter 'm'

Answer:
2