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 man holding a baseball bat an playing baseball'. Find frequency of the letter 'l'

Answer: 6


Question: Sentence: 'various plates sit on a table containing meat, broccoli, and other foods'. Find frequency of the letter 'a'

Answer:
7