Being disruptive in class? If your efforts to calm the student and resume teaching fail, call the campus police (formerly "public safety") at 510-885-3791 and have them ejected, if they will not leave at your request. Information is available at Dealing with Disruptive Student Behavior.
Cheating? Contact Student Judicial Affairs or your department chairperson. Information about the judicial process is at Student Conduct Rights.
Saying I am being unfair (either in grading or in teaching the class)? Refer the student to the Department Chairperson.