The number of significant figures in $4.870 \ m$ is

State the number of significant figures in the following:
$(a)$ $0.007 \;m^{2}$
$(b)$ $2.64 \times 10^{24} \;kg$
$(c)$ $0.2370 \;g \;cm^{-3}$
$(d)$ $6.320 \;J$
$(e)$ $6.032 \;N \;m^{-2}$
$(f)$ $0.0006032 \;m^{2}$

"Trailing zeros in a number without a decimal point are not significant." Show that this statement is not always true.

If the side length of a cube is $7.203 \ m$,then its volume is ............ $m^3$.

For the four sets of three measured physical quantities as given below,which of the following options is correct?
$(i)$ $A_{1}=24.36, B_{1}=0.0724, C_{1}=256.2$
$(ii)$ $A_{2}=24.44, B_{2}=16.082, C_{2}=240.2$
$(iii)$ $A_{3}=25.2, B_{3}=19.2812, C_{3}=236.183$
$(iv)$ $A_{4}=25, B_{4}=236.191, C_{4}=19.5$

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