$500=5\cdot 100=5\cdot {10}^2$

$60000=6\cdot 10000=6\cdot {10}^4$

$3=3\cdot 1=3\cdot {10}^0$

$0,002=2\cdot 0,001=2\cdot {10}^{-3}$  

$0,007=7\cdot 0,001=7\cdot {10}^{-3}$