The current $i$ in the circuit will be:

The lungs are covered by which of the following?

The accessory glands of the human male reproductive system are:

Which of the following ions is paramagnetic?

$A$ train moving at a speed of $220\, ms^{-1}$ towards a stationary object,emits a sound of frequency $1000\, Hz$. Some of the sound reaching the object gets reflected back to the train as echo. The frequency of the echo as detected by the driver of the train is .... $Hz$ (speed of sound in air is $330\, ms^{-1}$)

At $27^{\circ} C$,$500 \ mL$ of helium diffuses in $30 \ minutes$. What is the time (in hours) taken for $1000 \ mL$ of $SO_2$ to diffuse under the same experimental conditions?