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 mixed bouquet of flowers in a glass vase set before a window'. Find frequency of the letter 'w'

Answer: 3

Question: Sentence: 'a blue bowl holding mashed bananas and oatmeal with a bottle of sugar and cinnamon sitting beside it'. Find frequency of the letter 'g'

Answer: 3

Question: Sentence: 'a tennis player holding a racket on a white background'. Find frequency of the letter 'n'

Answer:
5