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 young woman dressed in green and black operating a remote control'. Find frequency of the letter 'r'

Answer: 5


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

Answer: 2


Question: Sentence: 'a table and chairs with an umbrella on the sidewalk'. Find frequency of the letter 'l'

Answer:
4