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 flying through the air on top of a skateboard'. Find frequency of the letter 'r'

Answer: 3


Question: Sentence: 'a double-decker bus covered in children's illustrations driving next to a van'. Find frequency of the letter 'a'

Answer: 4


Question: Sentence: 'a man wearing a white turban on his head'. Find frequency of the letter 'i'

Answer:
3