Consider the following:
$A) 0.0025$
$B) 500.0$
$C) 2.0034$
Number of significant figures in $A, B$ and $C$ respectively,are

The sum of three values $12.0$, $19.034$ and $2.0143$ is equal to $X$. The number of significant figures in $X$ is

$2 \times 10^{8}$ atoms of carbon are arranged side by side. Calculate the radius of a carbon atom if the length of this arrangement is $2.4 \, cm$.

Fill in the blanks given below:
$(i)$ The instrument used to measure the mass of a single atom is .......
$(ii)$ The sum of the mole fractions of all components in a solution is always .......
$(iii)$ The $SI$ unit of volume is ........

$81.4 \ g$ sample of ethyl alcohol contains $0.002 \ g$ of water. The amount of pure ethyl alcohol in $g$ to the proper number of significant figures is:

How many seconds are there in $2$ days (in $s$)?