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 person standing on a blue towel'. Find frequency of the letter 'n'

Answer: 4


Question: Sentence: 'a woman walking on a shore next to a river'. Find frequency of the letter 'v'

Answer: 1


Question: Sentence: 'a plate of food that includes a sandwich and shoe string fries'. Find frequency of the letter 'i'

Answer:
4