1. Consider the following description of some university where professors teach courses in which
students can enroll. A teacher has a name, address, phone number, email address, and salary. A
student has also a name, phone number etc., but no salary (sorry). A student also gets some
marks by enrolling in each course. Each course has a name and a number. When a student is
enrolled in a course, the marks for this enrollment are recorded and the current average as well as
the final marks can be obtained from the enrollment. From a student one can obtain a list of
courses he or she is enrolled in. Each course has at least one and at most three teachers. There are
two types of courses: undergraduate and graduate. Students cannot withdraw from an
undergraduate course once enrolled, but from a graduate course they can. Draw a class diagram
for this university. Include the necessary class associations and their multiplicities. Add attributes
and methods when necessary. You do not have to include getters and setters for attributes. Also
visibility modifiers (public, private, etc.) are not required