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 man sitting on a motorcycle near two other men'. Find frequency of the letter 'r'

Answer: 3


Question: Sentence: 'man in red shirt with black suitcase standing outside of building'. Find frequency of the letter 'i'

Answer: 8


Question: Sentence: 'a man holding a bat at a baseball field'. Find frequency of the letter 'a'

Answer:
8