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 computers and a laptop set up on a desk'. Find frequency of the letter 'r'

Answer: 1

Question: Sentence: 'two young ladies that are dancing in the room together'. Find frequency of the letter 'a'

Answer: 4

Question: Sentence: 'man in air skateboarding on street with building'. Find frequency of the letter 't'

Answer:
4