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 girl playing with a frisbee while people watch'. Find frequency of the letter 'e'

Answer: 5


Question: Sentence: 'this marketplace has a lot of fresh fruit and vegetables'. Find frequency of the letter 'v'

Answer: 1


Question: Sentence: 'adult running with with surfboard on beach with ocean'. Find frequency of the letter 'a'

Answer:
4