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 with a large grey and black beard and glasses and a tie'. Find frequency of the letter 'e'

Answer: 5


Question: Sentence: 'two elephants walking on cement next to wall'. Find frequency of the letter 'n'

Answer: 5


Question: Sentence: 'a man on skis smiles into the camera'. Find frequency of the letter 'o'

Answer:
2