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: 'there is a woman pointing at something with her dog'. Find frequency of the letter 'i'

Answer: 5

Question: Sentence: 'a large grass pasture land with sheep grazing on grass'. Find frequency of the letter 'a'

Answer: 7

Question: Sentence: 'a red and white fire hydrant sitting in the middle of a forest'. Find frequency of the letter 's'

Answer:
2