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 little boy that has a toothbrush in his mouth'. Find frequency of the letter 'r'

Answer: 1


Question: Sentence: 'a man standing in front of a statue near a metal pole'. Find frequency of the letter 'f'

Answer: 2


Question: Sentence: 'a double decker metro bus stopped at a covered bus stop loading passengers'. Find frequency of the letter 'e'

Answer:
9