How to say no to the boss?

Do you like your boss?

I think most people will say no to such a question. Employees are always having problem dealing with their supervisors, so am I.
I am currently working in an office as a part-time assistant. I have been holding this job for almost 2 years. We got a new boss about 3 monthes ago. He began to set up new rules and change procedures of the working processes befor he has some senses of what is going on in this office. Eventually, he gives everyone a hard time and slow down the productivity. He keeps push works and responsibility to his people. He calls other full-time workers to run into his room for urgence but they were just told to make a piece of copy, using the machine next to his door. He asked a pregnant worker to pack and move boxes of files for his new room. He doesn'y trust on his people, especially women. Everyone complains behid him. Ton of e-mails were floating around the office aeguing for some little peoblems.
However, he is the boss. He is the one manage the office. How to say no to such a supervisor? What chould we do to disagree without being disagreeable?