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 crowd of people skiing and enjoying the snow'. Find frequency of the letter 'o'

Answer: 5


Question: Sentence: 'a knife a cutting board some bananas and a toaster'. Find frequency of the letter 'i'

Answer: 2


Question: Sentence: 'the train has stopped on the railroad tracks'. Find frequency of the letter 'a'

Answer:
5