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 man sitting inside a green military truck talking to someone'. Find frequency of the letter 'i'

Answer: 7


Question: Sentence: 'a closet with a fan, luggage and various boxes'. Find frequency of the letter 'a'

Answer: 6


Question: Sentence: 'a birthday cake for a thirteen year old'. Find frequency of the letter 'e'

Answer:
4