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 person is performing a stunt on a snowboard'. Find frequency of the letter 'p'

Answer: 2


Question: Sentence: 'a small boat travels on the water next to the shore'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a red helicopter with a person hanging from the side'. Find frequency of the letter 'r'

Answer:
4