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: 'the sun goes down over a bike tied to a bench at the beach'. Find frequency of the letter 't'

Answer: 5


Question: Sentence: 'a train station with a train pulling into the platform'. Find frequency of the letter 'i'

Answer: 6


Question: Sentence: 'a big billboard is painted onto the side of a brick building'. Find frequency of the letter 'b'

Answer:
5