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: 'this yellow fire hydrant sits in a grass field'. Find frequency of the letter 'i'

Answer: 5


Question: Sentence: 'a red stop sign with street signs above it'. Find frequency of the letter 't'

Answer: 5


Question: Sentence: 'this is a sign in front of a large cathedral'. Find frequency of the letter 'a'

Answer:
5