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

Answer: 2


Question: Sentence: 'an image of a cautionary construction sign'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a dirty bathroom with the door open'. Find frequency of the letter 'i'

Answer:
2