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: 'decorated baseball cake in a clear plastic box'. Find frequency of the letter 'k'

Answer: 1

Question: Sentence: 'two persons standing outside a moving sub train'. Find frequency of the letter 'a'

Answer: 3

Question: Sentence: 'a group of people walking on a busy city street near motorcycles'. Find frequency of the letter 'e'

Answer:
6