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 flying through the air on a bicycle'. Find frequency of the letter 'u'

Answer: 1


Question: Sentence: 'people fishing and enlarge mountainlake with trees lining the shoreline'. Find frequency of the letter 't'

Answer: 4


Question: Sentence: 'a double decker bus filled with passengers passes a bench as drives down a city street'. Find frequency of the letter 'a'

Answer:
6