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 standing in front of a green train'. Find frequency of the letter 'g'

Answer: 2


Question: Sentence: 'a bird on a tree is flapping its wings'. Find frequency of the letter 'o'

Answer: 1


Question: Sentence: 'a large giraffe poses for a close-up photos'. Find frequency of the letter 'r'

Answer:
3