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: 'young boy flying kite in large field at outdoor event'. Find frequency of the letter 'y'

Answer: 3


Question: Sentence: 'a man and several white red and blue airplanes'. Find frequency of the letter 'u'

Answer: 1


Question: Sentence: 'a lady taking a picture of orange colored roses'. Find frequency of the letter 'a'

Answer:
5