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: 'two people in a snowy place near a wooden fence'. Find frequency of the letter 'n'

Answer: 5

Question: Sentence: 'a man and a woman are playing on the wii'. Find frequency of the letter 'p'

Answer:
1