<u>Answer:
</u>
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.
Explanation:
In the United States, a political action committee (PAC) is a 527 organization that pools campaign contributions from members and donates those funds to campaigns for or against candidates, ballot initiatives, or legislation. ... At the state level, an organization becomes a PAC according to the state's election laws.