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 commercial airline airplane flies above the clouds'. Find frequency of the letter 'n'

Answer: 3

Question: Sentence: 'a white bathroom sink sitting next to a toilet'. Find frequency of the letter 'i'

Answer: 5

Question: Sentence: 'a bowl of oranges sitting on a wooden cutting board'. Find frequency of the letter 'g'

Answer:
3