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 picture of two men on a motorcycle in front of a railroad track'. Find frequency of the letter 'n'

Answer: 4


Question: Sentence: 'a burning wood stove has a tea pot sitting on top of it and is full of wood'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a cat laying on top of a chair next to a teddy bear'. Find frequency of the letter 'a'

Answer:
7