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: 'two pepperoni pizzas and a cup on a counter'. Find frequency of the letter 'u'

Answer: 2


Question: Sentence: 'one man grabbing another at a table while laughing'. Find frequency of the letter 'n'

Answer: 5


Question: Sentence: 'a group of people gathered around a table cutting a cake'. Find frequency of the letter 'a'

Answer:
7