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 couple of girls are hanging out at a restaurant'. Find frequency of the letter 'l'

Answer: 2


Question: Sentence: 'a man with headphones on is hunched over a sink while being recorded'. Find frequency of the letter 'd'

Answer: 4


Question: Sentence: 'dog in the air catching a frisbee over a swimming pool'. Find frequency of the letter 'a'

Answer:
4