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 sheep in a field in front of other sheep'. Find frequency of the letter 'f'

Answer: 3


Question: Sentence: 'a tennis player after hitting a shot back to the other side of the court'. Find frequency of the letter 'n'

Answer: 3


Question: Sentence: 'the boat is travelling out into the waters'. Find frequency of the letter 'w'

Answer:
1