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 man holding a brown paper bag kite'. Find frequency of the letter 'b'

Answer: 2

Question: Sentence: 'an old woman is holding her cat in front of a camera'. Find frequency of the letter 'r'

Answer: 3

Question: Sentence: 'a gray elephant is in a grassy field'. Find frequency of the letter 'e'

Answer:
3