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: 'three young people goofing around; one of the guys has a football, the girl has a teddy bear'. Find frequency of the letter 'd'

Answer: 3

Question: Sentence: 'three young children playing with a ball in front of a huge bridge'. Find frequency of the letter 'e'

Answer: 5

Question: Sentence: 'a group of men walking away from a propeller plane'. Find frequency of the letter 'e'

Answer:
4