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 holding a frisbee high into the air'. Find frequency of the letter 'a'

Answer: 4

Question: Sentence: 'a toasted sub sandwich is next to a salad'. Find frequency of the letter 'a'

Answer: 6

Question: Sentence: 'two bridges across a river, one bridge only goes half way'. Find frequency of the letter 'i'

Answer:
3