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 gray elephant is in a grassy field'. Find frequency of the letter 'e'

Answer: 3


Question: Sentence: 'a woman with short, brown hair is looking into a circular mirror and holding a camera up to her cheek'. Find frequency of the letter 'e'

Answer: 4


Question: Sentence: 'a group of people hunched on the ground while a dog catches a frisbee above them and other people watch'. Find frequency of the letter 'f'

Answer:
2