161043
The ridge forms part of the east/west watershed between the River Severn and the River Trent , with rainfall on the western side going to the Bristol Channel via the Severn , and rainfall on the eastern side ending up in the North sea via the Trent .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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