<u>Answer:
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The study carried out by Dr. Xu is a randomized controlled study.
<u>Explanation:</u>
- For the sake of determination of how the results of the students change by doing certain changes to the examination pattern, Dr. Xu devised that the change is considerably evident.
 - Dr. Xu provided and intervention in the process of exam in the form of guides which helped the students to score better later. Hence, from the standard of conduct of the study, it can be said to be a randomized controlled study.
 
 
        
             
        
        
        
people accused of crimes have specific constitutional protections
 
        
                    
             
        
        
        
With regard to the culture clashes in different nations and communities, use of the contact hypothesis theory could help to ease tensions. 
In the contact hypothesis theory, which is credited to Gordon Allport, is the ability for two or more cultures to coexist peacefully through meaningful and thoughtful interaction in order to reduce prejudice. To ensure successful contact, it is recommended that: both groups receive equal status of importance with minimal differences in characteristics, backgrounds, and qualities; groups work towards achieving a common goal which is equally beneficial to both groups; there is cooperation from all subjects in each group; support from local authorities of laws/government and customs; personal interaction between members of opposing groups. 
Potential outcomes for successful tourist-host contact include: relaxed attitudes, understanding, a mutual appreciation for the opposing culture's values, positive interactions wherein cultures are respected mutually, increased active communication to ensure both parties are satisfied and can co-exist peacefully, and perceiving the opposing culture as equally important. 
 
        
             
        
        
        
The correct answer is; criminal liability.
Further Explanation:
A server can face jail time and being fined for serving alcohol to an underage guest. The most likely charge they will face is a criminal liability charge. Since the servers are trained about serving alcohol and checking identification they are liable for doing their job. 
Serving any alcohol product to someone underage is illegal in the United States. The age that a person can legally buy alcohol is 21 years of age. If the server has given an underage person alcohol and that person drives and is in an accident the server is going to be charged also, because they are the ones responsible for serving the underage person. In addition to being charged with a crime, the person can be sued, banned from working in an establishment that has alcohol, and fired from their job.
Learn more about underage drinking at brainly.com/question/11824838
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