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 ready to eat pizza on a rack'. Find frequency of the letter 'r'

Answer: 2


Question: Sentence: 'a man riding a skateboard up the side of a ramp'. Find frequency of the letter 'u'

Answer: 1


Question: Sentence: 'the young school boys are posing for the camera'. Find frequency of the letter 's'

Answer:
3