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: 'an image of a cautionary construction sign'. Find frequency of the letter 'a'

Answer: 5

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

Answer: 6

Question: Sentence: 'a group of sheared and natural sheep in a green field'. Find frequency of the letter 'e'

Answer:
7