In three to four sentences, describe why CEOs (the chief executive officers, that is, the leaders of large companies) make very high salaries, while their administrative assistants make much less.

Well, CEOs are on the top of the food chain. It takes a lot of work and ambition to become one, and once they are one, CEOs accept a huge amount of responsibility - that means having to take blame if things go wrong and having more tasks to complete such as having to attend numerous meetings, make decisions. They are also on the board of directors.

Assistants do not have to do as much, they likely won't have that much responsibility or experience, their tasks revolve around ensuring meetings are scheduled and performing other ad-hoc duties.