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 bunch of green bananas is hanging on a tree'. Find frequency of the letter 'n'

Answer: 7


Question: Sentence: 'a person dressed all in black snowboarding down a slope'. Find frequency of the letter 'e'

Answer: 4


Question: Sentence: 'a busy street has many people walking and biking around'. Find frequency of the letter 'k'

Answer:
2