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 train going over a bridge with some buildings in the background'. Find frequency of the letter 'd'

Answer: 3


Question: Sentence: 'group of snowboarders on a snowy trail overlooking a mountain'. Find frequency of the letter 'r'

Answer: 5


Question: Sentence: 'a man and two women posing for a picture in front of a christmas tree'. Find frequency of the letter 't'

Answer:
5