The figure shows two containers $P$ and $Q$ with the same base area $A$,each filled to the same height with the same liquid. Select the correct alternative.

$A$ tank of oil has a height of $4 \,m$ and a density of $850 \,kg \,m^{-3}$. The gauge pressure at the bottom of the tank is (Given: $1 \,atm = 10^5 \,Pa$,Acceleration due to gravity $g = 10 \,m \,s^{-2}$) (in $\,kPa$)

$A$ manometer reads the pressure of a gas in an enclosure as shown in the figure. The absolute and gauge pressure of the gas in $cm$ of mercury are (Take atmospheric pressure $= 76\,cm$ of mercury)

$A$ container of height $10 \, cm$ is filled with water. There is a hole at the bottom. Find the pressure difference between points at the top and the bottom.

Variation of atmospheric pressure with height from the Earth is ................

Torricelli's barometer used mercury. Pascal duplicated it using French wine of density $984 \; kg \; m^{-3}$. Determine the height (in $m$) of the wine column for normal atmospheric pressure.