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 man opening up a package sitting on a couch'. Find frequency of the letter 'n'

Answer: 5


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

Answer: 1


Question: Sentence: 'an image of a man and his kids in front of a birthday cake'. Find frequency of the letter 'n'

Answer:
5