In a capillary tube of radius 'R', a straight thin metal wire of radius 'r' is inserted symmetrically and one end of the combination is dipped vertically in water such that lower end of the capillary and thin wire are at same level. If 'T' is the surface tension of water and '$\rho$' is the density of water then the rise of water in the capillary is

Due to surface tension, the excess pressure inside a smaller drop is $9$ units. If $27$ smaller drops combine then excess pressure inside the bigger drop is

Two rain drops of same radius '$r$' falling with same terminal velocity '$V$' merge and form bigger drop of radius '$R$'. The terminal velocity of big drop is

A spherical ball of radius $1$ mm and density $10.5$ g/cc is dropped in glycerine of coefficient of viscosity $9.8$ poise and density $1.5$ g/cc. Viscous force on the ball when it attains constant velocity is $3696 \times 10^{-x}$ N. The value of $x$ is
(Given, $g = 9.8 \text{ m}/\text{s}^2$ and $\pi = \dfrac{22}{7}$)