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 half eaten doughnut in a persons hand'. Find frequency of the letter 'h'

Answer: 3


Question: Sentence: 'a herd of giraffe walking across a field'. Find frequency of the letter 'k'

Answer: 1


Question: Sentence: 'a skateboarder does a handstand trick on a skate-ramp'. Find frequency of the letter 'r'

Answer:
4