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: 'a batter, catcher and umpire waiting for the pitch and a major league baseball game'. Find frequency of the letter 'c'

Answer: 3


Question: Sentence: 'a cat laying onto of an unzipped suitcase'. Find frequency of the letter 'o'

Answer:
3