Using Properties of Logarithms

We want to write the number $1$ on the form $\log (a),$ for some number $a.$ Here we can use the rule $$\log \left(10^m\right)=m$$ to find the number $a.$ With $m=1$ we see that $a=10^1.$ Therefore we can write as follows. $$1=\log (10)$$

We can use the same reasoning as in Part A. Find the power of ten which has the exponent $6.$ It's the same as $10^6,$ and so $$6=\log \left(10^6\right).$$

Now we have a negative number, however, it does not matter. A power of ten with the exponent $\text{-}3$ is $10^{\text{-}3}.$ That means $$\text{-}3=\log (10^{\text{-}3}).$$