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 person is holding a chocolate doughnut with rainbow sprinkles'. Find frequency of the letter 's'

Answer: 4


Question: Sentence: 'a crowd of people standing in front of a green train'. Find frequency of the letter 'g'

Answer: 2


Question: Sentence: 'a person with a snowboard attached to him who is sitting on the snow with a man standing next to him'. Find frequency of the letter 'w'

Answer:
5