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 girl sits on a surfboard and smiles'. Find frequency of the letter 'i'

Answer: 3


Question: Sentence: 'a bunch of cows that are in the field'. Find frequency of the letter 'a'

Answer: 3


Question: Sentence: 'two brown bowls filled with food sitting on a counter'. Find frequency of the letter 'f'

Answer:
2