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 group of people stand inside of a big room'. Find frequency of the letter 'o'

Answer: 6


Question: Sentence: 'a person that is looking out his window'. Find frequency of the letter 'n'

Answer: 3


Question: Sentence: 'the utility tray is pulled out from the back of a large appliance'. Find frequency of the letter 'l'

Answer:
5