The number of significant figures in $200.40$ is

The side length of a cube is $1.2 \times 10^{-2} \ m$. Calculate its volume.

From the point of view of significant figures,which of the following is/are correct?
$(i)\ 11.3 \ cm + 4 \ cm = 15.3 \ cm$
$(ii)\ 4.53 \ m - 1.2 \ m = 3.3 \ m$
$(iii)\ 5.45 \ kg - 3.2 \ kg = 2.25 \ kg$
$(iv)\ 84.8 \ cm + 48.6 \ cm = 133 \ cm$

Match the numbers in Column-$I$ with the number of significant figures in Column-$II$.

Column-$I$	Column-$II$
$(1)$ $2.85 \times 10^{26} \ kg$	$(a)$ $1$
$(2)$ $0.009 \ m^2$	$(b)$ $2$
$(3)$ $0.060 \ s$	$(c)$ $3$

The number of significant figures in the simplification of $\frac{0.501}{0.05}(0.312-0.03)$ is

If the length of a rod is measured as $830600 \ mm$,then the number of significant figures in the measurement is