Is variation all about apparent differnce ? Or is it about some subtle differences as well that we most often overlook?

Collect the information about the base area and stability of some objects with different shapes and write a report.

Can we say that all free electrons move in the same direction in a conductor when some potential difference is applied across it ?

Answer the following : How did we obtain all the information about the universe ? If we look at the sky at night we see only planets and stars , then how did we get information about the other components of the universe ?