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: 'two zebras feed on a plant through some wire mesh'. Find frequency of the letter 'o'

Answer: 4


Question: Sentence: 'a surfer is in the middle of an ocean wave'. Find frequency of the letter 'i'

Answer: 3


Question: Sentence: 'a group of elephants walking by a tree in the jungle'. Find frequency of the letter 'n'

Answer:
4