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 laptop computer with pictures of giraffes on the homescreen'. Find frequency of the letter 'o'

Answer: 5


Question: Sentence: 'a construction sign is displayed on a street'. Find frequency of the letter 'i'

Answer: 4


Question: Sentence: 'a airplane sitting on a runway at a small airport'. Find frequency of the letter 'n'

Answer:
4