Final answer:
An 18-year-old unrestrained passenger with multiple traumatic injuries from a motor vehicle crash and a blood pressure of 80/60 mm Hg should be treated at a Level I trauma center.
Step-by-step explanation:
Based on the provided information, the patient is an 18-year-old unrestrained passenger who sustained multiple traumatic injuries from a motor vehicle crash and has a blood pressure of 80/60 mm Hg. Given these critical conditions, the patient should be treated at a Level I trauma center. Level I trauma centers have the resources and expertise necessary to provide the highest level of care for patients with severe injuries.