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 man holding a baseball bat an playing baseball'. Find frequency of the letter 'l'

Answer: 6

Question: Sentence: 'a close up of a bird on the outside window sill'. Find frequency of the letter 'c'

Answer: 1

Question: Sentence: 'a large rock mountain sitting in the middle of the desert'. Find frequency of the letter 't'

Answer:
6