In the given circuit, the current flowing through it is: (in $ A$)

For the energy levels in an atom,which one of the following statements is correct?

The foci of the ellipse $\frac{x^2}{16} + \frac{y^2}{b^2} = 1$ and the hyperbola $\frac{x^2}{144} - \frac{y^2}{81} = \frac{1}{25}$ coincide. Then the value of $b^2$ is -

In gel electrophoresis,the separated bands of $DNA$ are cut out and extracted from the gel piece. This step is called

Which of the following compounds is soluble in benzene but almost insoluble in water?

When one end of a capillary tube is dipped in water,the height of the water column is $h$. The upward force of $105 \text{ dyne}$ due to surface tension is balanced by the force due to the weight of the water column. What is the inner circumference of the capillary (in $text{ cm}$)? (Surface tension of water $= 7 \times 10^{-2} \text{ N m}^{-1}$)