On heating a liquid,the refractive index generally

The refractive indices of glass and water with respect to air are $3/2$ and $4/3$ respectively. The refractive index of glass with respect to water will be

$A$ ray of light travels from air to water to glass and again from glass to air. The refractive index of water with respect to air is $x$,glass with respect to water is $y$,and air with respect to glass is $z$. Which one of the following is correct?

$A$ tank is filled with water to a height of $16 \text{ cm}$. Find the apparent depth of a needle lying at the bottom of the tank as measured by a microscope. The refractive index of water $(\mu_{w})$ is $\frac{4}{3}$. (in $\text{ cm}$)

Light travels through water in a beaker. The height of the water column is $h$. If the refractive index of water is $\mu_{w}$ and $C$ is the velocity of light in air,the time taken by light to travel through the water will be:

As shown in the figure,after passing through medium $1$,the speed of light $v_{2}$ in medium $2$ will be $..... \times 10^{8} \, ms^{-1}$. (Given $c = 3 \times 10^{8} \, ms^{-1}$)