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 and several white red and blue airplanes'. Find frequency of the letter 'u'

Answer: 1


Question: Sentence: 'a herd of giraffes in tall african grass'. Find frequency of the letter 'a'

Answer: 6


Question: Sentence: 'large group of food sitting on top of a table with white dishes'. Find frequency of the letter 'o'

Answer:
7