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 baby calf has a tag on its right ear'. Find frequency of the letter 'n'

Answer: 1

Question: Sentence: 'a blue fire hydrant painted on the bottom of it'. Find frequency of the letter 'h'

Answer:
2