If it takes 5 minutes to fill a 15 litre bucket from a water tap of diameter $\frac{2}{\sqrt{\pi }} cm$ then the Reynolds number for the flow is (density of water = ${10}^{3\mathrm{ }}kg/m^3 and viscosity of water={10}^{-3} Pa.s$ ) close to:

A cylindrical block of wood (density = $650 \mathrm{kg} {\mathrm{m}}^{-3}$), of base area $30\mathrm{ }{\mathrm{cm}}^2$ and height $54 \mathrm{cm}$, floats in a liquid of density $900 \mathrm{kg} {\mathrm{m}}^{-3}$. The block is depressed slightly and then released. The time period of the resulting oscillations of the block would be equal to that of a simple pendulum of length (nearly) :

In the diagram shown, the difference in the two tubes of the manometer is $5 \mathrm{cm}$, the cross-section of the tube at $A$ and $B$ is $6 {\mathrm{mm}}^2$ and $10 {\mathrm{mm}}^2$ respectively. The rate at which water flows through the tube is $\left(g=10 \mathrm{m} {\mathrm{s}}^{-2}\right)$