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 little dog on a table while a dog groomer cuts its fur'. Find frequency of the letter 'r'

Answer: 3


Question: Sentence: 'two hot dogs on buns next to a glass of water'. Find frequency of the letter 't'

Answer:
5