Can't open View->DBA Menu in SQL Developer (Oracle 12C Standard Edition Installed)

Question

I have installed Oracle 12C Standard Edition. Everything works fine there. I have also connected the Oracle SQL Developer Client 4.0. From that I can access the tables, indexes

Answer 1

Selecting the View->DBA menu item displays the "DBA" panel, on the left side of the SQL Developer window and somewhere below the "Connections" panel; the exact placement may vary a bit depending on which other panels you have displayed:

You then need to add a connection in that window' if you click the green plus sign you can choose an existing connection to add to this panel. Once you've done that you can expand the sections to see the tablespaces: