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 that has a kite in the air'. Find frequency of the letter 'r'

Answer: 2

Question: Sentence: 'a grapefruit, toast, coffee and other items are on a tray'. Find frequency of the letter 't'

Answer: 6

Question: Sentence: 'an airplane at its terminal as the sun sets'. Find frequency of the letter 'e'

Answer:
4