Misc: A device used to change the voltage of alternating currents is a ______?

Questions

It was quite common for the men of Ancient Greece to exercise in public ......?

John Paul Getty, once the richest man in the world, had a ______ in his mansion?

Iceland is the world's oldest functioning?

The national flag of _____ was designed by Napoleon Bonaparte?

The Matami Tribe of West Africa play a version of football, the only difference being that they use a ____ ____ instead of a more normal ball?