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 girl playing with a frisbee while people watch'. Find frequency of the letter 'e'

Answer: 5


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

Answer: 3


Question: Sentence: 'a man holding a toilet seat on a square toilet in a bathroom'. Find frequency of the letter 's'

Answer:
2