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 in a black shirt prepares to catch a frisbee'. Find frequency of the letter 'f'

Answer: 1


Question: Sentence: 'small black bird with red on its head standing on a tree branch'. Find frequency of the letter 'b'

Answer: 3


Question: Sentence: 'several wine glasses placed on a glass table filled with different wines'. Find frequency of the letter 'd'

Answer:
3