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: 'wooden and black bench on the side of the road'. Find frequency of the letter 'a'

Answer: 3

Question: Sentence: 'a gray airplane with metal petals on the wings takes off from an airport'. Find frequency of the letter 'i'

Answer: 4

Question: Sentence: 'a collection of folded dollar bills, multicolored ear plugs, toothbrushes, pills and spoons neatly arranged in rows'. Find frequency of the letter 'u'

Answer:
3