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 burning wood stove has a tea pot sitting on top of it and is full of wood'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a small white dog looking out a car window'. Find frequency of the letter 'l'

Answer: 3


Question: Sentence: 'a young kid smiling while holding a banana'. Find frequency of the letter 'y'

Answer:
1