Which property is demonstrated? (m2)3 = m6

In the case of , the power is raised to another power and these are multiplied together to simplify the term. This property is called the power of a power property.

The power of a power property just tells us that when the power is raised to another power, we can simply multiply these powers together. Let's take for example the given. , when expounded, is just equal to:
.

Same will hold true for all powers raised to another power.