Please draw a clear ER diagram with explanation and show if it's mandatory or optional or unspecified.

 

2. Do not use MS Word or MS PowerPoint to draw the ER diagram. Use tools such as https://erdplus.com/, https://www.smartdraw.com, or https://app.diagrams.net/. The Question Draw a completely labeled ER diagram for the following description. Use the (min, max) notation to specify cardinality ratios and participation constraints. "A medical research group is keeping a database about its published papers relating to viruses. The group keeps details about institutes who produce papers. For every institute, the database stores its name (unique), address (which consists of apartment number, street name, city, & country), and type. For every paper produced by an institute, the database stores details about its number (unique), title, journal name, volume number, issue number and year. A paper may refer to other papers, and it has several authors. For every author, the database stores his/her number (unique), name, nationality and date of birth. A paper writes details about viruses and a virus can be described by many papers. For every virus, the database stores its name (unique), and description. A paper is funded by one contract, but a contract may fund several papers. A contract has a number (unique), amount, start-date and end-date.