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 couple of boys in a field playing baseball'. Find frequency of the letter 'i'

Answer: 3


Question: Sentence: 'man in air skateboarding on street with building'. Find frequency of the letter 't'

Answer: 4


Question: Sentence: 'there are many boxes of different fruits at a market'. Find frequency of the letter 'y'

Answer:
1