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: 'young girl playing with refrigerator magnet while kneeling on floor'. Find frequency of the letter 'n'

Answer: 6

Question: Sentence: 'two bears swim in a blue pool of water'. Find frequency of the letter 'o'

Answer: 4

Question: Sentence: 'the boy is determined to show everyone how good he is on his skateboard'. Find frequency of the letter 'v'

Answer:
1