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: 'an old glass vase containing flowers on a glass table'. Find frequency of the letter 'b'

Answer: 1


Question: Sentence: 'two computers and a laptop set up on a desk'. Find frequency of the letter 'r'

Answer: 1


Question: Sentence: 'a train with passenger cars stops at a train station'. Find frequency of the letter 'a'

Answer:
8