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 blue tripocal bird is perched on a wooden fence'. Find frequency of the letter 'd'

Answer: 3


Question: Sentence: 'a man sitting on a motorcycle near two other men'. Find frequency of the letter 'r'

Answer: 3


Question: Sentence: 'a group of people riding skis on a snowy surface'. Find frequency of the letter 'p'

Answer:
3