Convert the following textual description to an entity$-$relationship diagram in UML notation. Please spend time differentiating between entities, attributes, relationships and values of attributes. If you are identifying a strong entity $-$ make sure you identify a primary key for it$.$ You are not required to use superclass$/$subclass hierarchy for any of these problems, but may choose to do so if you wish. Remember, weak entities do not have a primary key. You are not required to use superclass$/$subclass hierarchy for any of these problems, but may choose to do so if you wish.

The world is composed of $7$ continents. A continent has a unique name and a current population. The names of the continents are: Africa, Antarctica, Asia, Europe, Australia$/$Oceania$,$ North America and South America. A country has a unique name, and a current population. Each continent is composed of $0$ to many countries. A country may be situated on $1$ to many continents.