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 gray airplane with metal petals on the wings takes off from an airport'. Find frequency of the letter 'i'

Answer: 4


Question: Sentence: 'a bus is driving on the street behind some cars'. Find frequency of the letter 'a'

Answer: 2


Question: Sentence: 'a plate of food with some corn, broccoli, and meat on it'. Find frequency of the letter 'd'

Answer:
2