Exercise $2($explain in detail please$)$: Aggregration versus composition

Recall composition is stronger than aggregation, in the sense that in a composite, if the whole goes away,

so does the part $($if the book goes away, so do all of its pages$)$; in an aggregate, parts may exist even if

the aggregate goes away $($if the library goes away, the books may still exist, if you think of the libray as an

aggregate of books$).$

Using the composition and aggregation, describe the reationship between:

The car and its wheels

The University and its Departments

Draw two simple class diagram, illustrating the scenarios above. If you are wondering about multiplicity, a

car must have precisely $4$ wheels, and a University must have at least one department.