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 silver train crossing the road on tracks'. Find frequency of the letter 'r'

Answer: 5


Question: Sentence: 'the skateboarder has on red and black sneakers and is riding a skateboard'. Find frequency of the letter 'g'

Answer: 1


Question: Sentence: 'a skateboarder doing a trick in front of a lighthouse'. Find frequency of the letter 't'

Answer:
4