Standards

2 Chronicles 3:3 - The foundation Solomon laid for building the temple of God was sixty cubits long and twenty cubits wide (using the cubit of the old standard).

I wonder what the difference was between the old standard cubit and the new standard cubit. We commonly say a cubit was the distance from fingertip to elbow, but that in and of itself isn't exact or precise and certainly not standard. I wonder what was used to standardize both the old and the new cubit. And why did someone see the need to change from one standard to the other?

I wonder if cubits were used in other cultures. Did that have anything to do with shifting to a new standard?

I wonder how long it took and how difficult it was to make the change. A king could just decree the change, but it might take a lot of work to put it into practice.

Metric system, anyone?