2. How can confidential data and information (such as the wages of individual employees) be kept confidential and
yet still be available to managers who need them?

Apotato i'm guessing?

The advantage of administering personality tests on employees is that it will allow the employer to know the mindset and personality of the employee. this will allow the employer to at least have an idea as to how the employee works and how his attitude in the workplace. the disadvantage is that it may make the employee a little anxious as to whether he would meet the personality requirements of the employer and whether he would be able to retain the job or not.