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 big bear walks through some grass'. Find frequency of the letter 'a'

Answer: 4


Question: Sentence: 'older man getting ready to swing his bat at a ball on a stand in front of a group of viewers'. Find frequency of the letter 'n'

Answer: 7


Question: Sentence: 'a group of boys and girls playing sports'. Find frequency of the letter 'l'

Answer:
2