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: 'men are riding on motorcycles with a man riding in their carriers'. Find frequency of the letter 'r'

Answer: 8

Question: Sentence: 'two zebra stand near the wooden posts on a building'. Find frequency of the letter 't'

Answer: 4

Question: Sentence: 'cars parked outside if a retail store'. Find frequency of the letter 'd'

Answer:
2