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: 'three elephants walk up a dirt trail from the water'. Find frequency of the letter 'l'

Answer: 3


Question: Sentence: 'two people in a snowy place near a wooden fence'. Find frequency of the letter 'n'

Answer: 5


Question: Sentence: 'a round table has some purple flowers on it'. Find frequency of the letter 'a'

Answer:
3