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: 'silhouette of person playing frisbee with moutain and sunset'. Find frequency of the letter 'i'

Answer: 5


Question: Sentence: 'slices of orange are arranged on a plate'. Find frequency of the letter 's'

Answer: 2


Question: Sentence: 'a long train traveling down train tracks near a river'. Find frequency of the letter 'l'

Answer:
2