Final answer:
According to researcher Robert Katz, one of the three principal skills acquired by experienced managers is Human skills. These skills involve working with and through other people.
Step-by-step explanation:
According to researcher Robert Katz, one of the three principal skills acquired by experienced managers is Human skills. Human skills refer to the ability to work with and through other people and to understand and motivate individuals and groups. These skills are crucial for effective leadership and building strong relationships within an organization.