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 gourmet looking hamburger with fries on a dining table with some wine'. Find frequency of the letter 't'

Answer: 4


Question: Sentence: 'a passenger train going down some tracks adjacent a city street'. Find frequency of the letter 't'

Answer:
6