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 bunch of cows that are in the field'. Find frequency of the letter 'a'

Answer: 3


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 number of people riding horses on a city street'. Find frequency of the letter 'b'

Answer:
1