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 bus is driving on the street behind some cars'. Find frequency of the letter 'a'

Answer: 2


Question: Sentence: 'a piece of film shows two street signs crossing each other'. Find frequency of the letter 'f'

Answer: 2


Question: Sentence: 'a boy laying on his side typing on a laptop computer'. Find frequency of the letter 'a'

Answer:
4