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 woman walking on a shore next to a river'. Find frequency of the letter 'v'

Answer: 1


Question: Sentence: 'man in a sleeping bag on the floor using a laptop computer'. Find frequency of the letter 'i'

Answer: 3


Question: Sentence: 'a large propeller airplane sitting on top of a tarmac'. Find frequency of the letter 'r'

Answer:
5