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 close up of a train on a track in the dark'. Find frequency of the letter 'a'

Answer: 6


Question: Sentence: 'a man swinging a bat while playing baseball'. Find frequency of the letter 'm'

Answer: 1


Question: Sentence: 'a room full of a group of people and their laptops'. Find frequency of the letter 'i'

Answer:
1