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 boy that is sitting at a table with pizza'. Find frequency of the letter 's'

Answer: 2


Question: Sentence: 'a person standing operating a cell phone in a room'. Find frequency of the letter 'n'

Answer: 6


Question: Sentence: 'a man in cowboy hat riding on a grey horse'. Find frequency of the letter 'i'

Answer:
3