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 giraffe shares a habitat with a zebra, an ostrich, and an okapi'. Find frequency of the letter 'e'

Answer: 3

Question: Sentence: 'a large group of motorcycles parked along a street'. Find frequency of the letter 'a'

Answer: 5

Question: Sentence: 'a person on a court with a tennis racket'. Find frequency of the letter 'n'

Answer:
4