Identify the carrier gas commonly used in gas chromatography.

The melting point of ice in Fahrenheit scale is........

Which of the following is correct?

Pressure is defined as the force acting per unit area of a surface. The $SI$ unit of pressure,$Pascal$ $(Pa)$,is defined as $1 \ Pa = 1 \ N \ m^{-2}$. If the mass of air at sea level is $1034 \ g \ cm^{-2}$,calculate the pressure in $Pascal$.

If an object weighs $275 \ lb$,what is its weight in $kg$? $(1 \ kg = 2.205 \ lb)$

Observe the following:
$I) 0.0063$
$II) 132.00$
$III) 1004$
The number of significant figures in $I, II$ and $III$ is respectively: