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 group of workers washing and cleaning fruits and vegetables'. Find frequency of the letter 'i'

Answer: 3


Question: Sentence: 'a person on a skateboard going down a ramp'. Find frequency of the letter 'n'

Answer: 4


Question: Sentence: 'several people at the beach surfing and playing in the water'. Find frequency of the letter 'i'

Answer:
3