$A$ river of salty water is flowing with a velocity $2 \,m/s$. If the density of the water is $1.2 \,g/cc$, then the kinetic energy of each cubic metre of water is

Why is skating possible on ice?

Given below are two statements:
$Statement$ $(I)$: Viscosity of gases is greater than that of liquids.
$Statement$ $(II)$: Surface tension of a liquid decreases due to the presence of insoluble impurities.
In the light of the above statements,choose the most appropriate answer from the options given below:

Fill in the blanks using the word$(s)$ from the list appended with each statement:
$(a)$ Surface tension of liquids generally . . . with temperatures (increases / decreases)
$(b)$ Viscosity of gases . . . with temperature,whereas viscosity of liquids . . . with temperature (increases / decreases)
$(c)$ For solids with elastic modulus of rigidity,the shearing force is proportional to . . .,while for fluids it is proportional to . . . (shear strain / rate of shear strain)
$(d)$ For a fluid in a steady flow,the increase in flow speed at a constriction follows (conservation of mass / Bernoulli's principle)
$(e)$ For the model of a plane in a wind tunnel,turbulence occurs at a . . . speed for turbulence for an actual plane (greater / smaller)

$A$ large number of droplets,each of radius $r$,coalesce to form a bigger drop of radius $R$. An engineer designs a machine so that the energy released in this process is converted into the kinetic energy of the drop. The velocity of the drop is ($T=$ surface tension,$\rho =$ density)

$A$ horizontal fire hose with a nozzle of cross-sectional area $\frac{5}{\sqrt{21}} \times 10^{-3} \text{ m}^2$ delivers a cubic metre of water in $10 \text{ s}$. What will be the maximum possible increase in the temperature of water while it hits a rigid wall (neglecting the effect of gravity) (in $^{\circ} \text{C}$)?