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 silver train crossing the road on tracks'. Find frequency of the letter 'r'

Answer: 5

Question: Sentence: 'a young woman dressed in green and black operating a remote control'. Find frequency of the letter 'r'

Answer: 5

Question: Sentence: 'a close up of a small car with a dog inside'. Find frequency of the letter 'a'

Answer:
5