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 herd of horses standing next to each other on a field'. Find frequency of the letter 'r'

Answer: 3

Question: Sentence: 'a person standing operating a cell phone in a room'. Find frequency of the letter 'n'

Answer: 6

Question: Sentence: 'a giraffe standing alone in a field looking back'. Find frequency of the letter 'c'

Answer:
1