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 riding a white surfboard on a large wave'. Find frequency of the letter 'a'

Answer: 7


Question: Sentence: 'a bowl of granola, dried fruit, and bananas'. Find frequency of the letter 'u'

Answer: 1


Question: Sentence: 'a mailbox laying in the middle of an empty street'. Find frequency of the letter 'i'

Answer:
4