7096
The command center monitors cameras through the canyon , and are used to control variable message signs to slow down or re-direct traffic , engage contraflow in the event of an accident , and dispatch tow trucks .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 None