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 group of people walking down a rain soaked street with umbrellas'. Find frequency of the letter 'w'

Answer: 3


Question: Sentence: 'two giraffes standing next to some trees'. Find frequency of the letter 'f'

Answer: 2


Question: Sentence: 'a black animal in dirt area below trees and rocks'. Find frequency of the letter 'n'

Answer:
3