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 person is riding in a cart pulled by a horse'. Find frequency of the letter 'a'

Answer: 4


Question: Sentence: 'a person holding a smart phone in their hands'. Find frequency of the letter 'r'

Answer:
3