$A$ cylinder of height $h$ is filled with water and is kept on a block of height $h/2$. The level of water in the cylinder is kept constant. Four holes numbered $1, 2, 3$ and $4$ are at the side of the cylinder and at heights $0, h/4, h/2$ and $3h/4$ from the base of the cylinder, respectively. When all four holes are opened together, the hole from which water will reach the farthest distance on the plane $PQ$ is the hole number:

$A$ water barrel having water up to a depth $d$ is placed on a table of height $h$. $A$ small hole is made on the wall of the barrel at its bottom. If the stream of water coming out of the hole falls on the ground at a horizontal distance $R$ from the barrel, then the value of $d$ is

$A$ tank is filled with water of density $1 \, g/cm^3$ and oil of density $0.9 \, g/cm^3$. The height of the water layer is $100 \, cm$ and the height of the oil layer is $400 \, cm$. If $g = 980 \, cm/s^2$,then the velocity of efflux from an opening in the bottom of the tank is

$A$ person in a lift is holding a water jar,which has a small hole at the lower end of its side. When the lift is at rest,the water jet coming out of the hole hits the floor of the lift at a distance $d$ of $1.2 \ m$ from the person. In the following,the state of the lift's motion is given in List-$I$ and the distance where the water jet hits the floor of the lift is given in List-$II$. Match the statements from List-$I$ with those in List-$II$ and select the correct answer using the code given below the lists.

List-$I$	List-$II$
$P$. Lift is accelerating vertically up.	$1$. $d = 1.2 \ m$
$Q$. Lift is accelerating vertically down with an acceleration less than the gravitational acceleration.	$2$. $d < 1.2 \ m$
$R$. Lift is moving vertically up with constant speed.	$3$. $d > 1.2 \ m$
$S$. Lift is falling freely.	$4$. No water leaks out of the jar.

There are two identical small holes of cross-sectional area $a$ on the opposite sides of a tank containing a liquid of density $\rho$. The difference in height between the holes is $h$. The tank is resting on a smooth horizontal surface. The horizontal force that must be applied to the tank to keep it in equilibrium is

Tanks $A$ and $B$ open at the top contain two different liquids up to a certain height. $A$ hole is made in the wall of each tank at a depth $h$ from the surface of the liquid. The area of the hole in $B$ is twice that of in $A$. If the liquid mass flux through each hole is equal, then the ratio of the densities of the liquids respectively, is