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: 'men standing in the grass with a frisbee'. Find frequency of the letter 'a'

Answer: 3

Question: Sentence: 'soccer players on opposite teams fight for control over a ball'. Find frequency of the letter 't'

Answer: 4

Question: Sentence: 'a traffic signal with a orange bicycle emblem on at the top'. Find frequency of the letter 'f'

Answer:
2