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 white bathroom sink sitting next to a toilet'. Find frequency of the letter 'i'

Answer: 5

Question: Sentence: 'there is a sandwich with a lot of meat cut in half'. Find frequency of the letter 'a'

Answer: 5

Question: Sentence: 'two baseball players standing on a field preparing to go to their assigned positions'. Find frequency of the letter 'a'

Answer:
7