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 elephant is in a grassy field'. Find frequency of the letter 'e'

Answer: 3


Question: Sentence: 'a cooked pizza on a silver platter with another in the background'. Find frequency of the letter 'e'

Answer: 5


Question: Sentence: 'different vehicles drive down street lined with buildings'. Find frequency of the letter 'w'

Answer:
2