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: 'a blue fire hydrant painted on the bottom of it'. Find frequency of the letter 'h'

Answer: 2


Question: Sentence: 'many motorcycles are parked in a line on a street'. Find frequency of the letter 'k'

Answer:
1