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 surfer is in the middle of an ocean wave'. Find frequency of the letter 'i'

Answer: 3


Question: Sentence: 'an audience watches as a bird spreads its wings'. Find frequency of the letter 'd'

Answer: 3


Question: Sentence: 'a couple of people standing outside with an umbrella'. Find frequency of the letter 'd'

Answer:
2