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 large grass pasture land with sheep grazing on grass'. Find frequency of the letter 'a'

Answer: 7


Question: Sentence: 'different sets of luggage in a baggage claim area'. Find frequency of the letter 'r'

Answer: 2


Question: Sentence: 'a train car at a standstill on railroad tracks'. Find frequency of the letter 's'

Answer:
3