Answer
(i) $2$
(ii) $5$
(iii) $-4$
Work Step by Step
On a logarithmic scale numbers are represented by their logarithms.
Basic property of logarithms: $\quad \log_{a}a^{x}=x$
(i) $\log 100=\log 10^{2}=2$
(ii) $\log 100,000=\log 10^{5}=5$
(iii) $\log 0.0001=\log 10^{-4}=-4$
