$\left(5^4\right)\ \times\ \left(5^8\right)\ =$  

 $4^{12\ }\times\ 4^8\ \times\ 4^2\ =$  

What is  $\frac{5^{2\ }}{5\text{}^2}$  ?

If an earthquake measures  $10^4$  , what does it measure on the Richter scale?

How much more powerful is an earthquake that measures 6.0 on the Richter scale than an earthquake that measures 4.0?