Living organisms can be distinguished from non-living things on the basis of which ability,excluding exceptions?

Two photons of energy $2.5 \ eV$ and $3.5 \ eV$ fall on a metal surface of work function $1.5 \ eV$. The ratio of the maximum velocities of the photoelectrons emitted from the metal surface is

In bryophytes and pteridophytes,transport of male gametes requires:

Match the following columns:

Column-$I$	Column-$II$
$a$. Superior Vena Cava	$p$. Carries deoxygenated blood to the lungs
$b$. Inferior Vena Cava	$q$. Carries oxygenated blood to the heart
$c$. Pulmonary Artery	$r$. Brings deoxygenated blood from lower body parts to the right atrium
$d$. Pulmonary Vein	$s$. Brings deoxygenated blood from upper body parts to the right atrium

The mass defect in a particular nuclear reaction is $0.3 ~g$. The amount of energy liberated in kilowatt hour is: (Velocity of light $= 3 \times 10^8 ~m/s$)

Two cylinders $A$ and $B$ fitted with pistons contain equal number of moles of an ideal monoatomic gas at $400 ~K$. The piston of $A$ is free to move while that of $B$ is held fixed. Same amount of heat energy is given to the gas in each cylinder. If the rise in temperature of the gas in $A$ is $42 ~K$, the rise in temperature of the gas in $B$ is (in $~K$)