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 giraffes walk together by a hill'. Find frequency of the letter 'b'

Answer: 1


Question: Sentence: 'a man with glasses adjusting his tie in a mirror'. Find frequency of the letter 's'

Answer: 5


Question: Sentence: 'a young boy holds a softball bat over his head indoors'. Find frequency of the letter 'o'

Answer:
7