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 fluffy white car looking in a mirror'. Find frequency of the letter 'k'

Answer: 1


Question: Sentence: 'a large cooked pizza on a dining table'. Find frequency of the letter 'n'

Answer: 3


Question: Sentence: 'a cart of luggage on a asphalt runway'. Find frequency of the letter 'n'

Answer:
2