How might a rock form very quickly, and then remain stable, or unchanged, for a very long period of time? Include a specific example in your explanation.

igneous rocks

Explanation:

One type of rock that forms very quickly would be igneous rocks. These are rocks that form after a volcanic eruption, where the molten magma melts everything into lava which then hardens shortly after. This creates a new rock that is a mixture of many other materials called Igneous rocks. Once hardened they usually remain stable and unchanged for a very long time until the next volcanic eruption. An example if the eruption of Tambora which after finishing has created lots of igneous rocks and has not erupted again since 1815.

the electrical  conductivity  of asolution  of an electrolyte is measured by determining the resistance of thesolution  between two flat or cylindrical electrodes separated by a fixed distance.

it's all four options.