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

Answer: 4


Question: Sentence: 'a little child looking up to a camera holding a cell phone'. Find frequency of the letter 'g'

Answer: 2


Question: Sentence: 'a man on a motorcycle driving in  heavy traffic'. Find frequency of the letter 'v'

Answer:
2