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: 'two men sitting quietly on a park bench'. Find frequency of the letter 'a'

Answer: 2


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 dog looking at a cake on the ground'. Find frequency of the letter 'a'

Answer:
4