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 small white plane sitting on top of the ocean'. Find frequency of the letter 'e'

Answer: 4


Question: Sentence: 'a few men walking through a market place'. Find frequency of the letter 'f'

Answer: 1


Question: Sentence: 'a lone zebra standing in a huge grassy field'. Find frequency of the letter 'e'

Answer:
4