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 bus with two floors belonging to london country'. Find frequency of the letter 't'

Answer: 4


Question: Sentence: 'a small boat and a large boat on a river near a city'. Find frequency of the letter 'a'

Answer: 10


Question: Sentence: 'a team of young boys playing softball in the street'. Find frequency of the letter 'o'

Answer:
4