Venus appears brighter than other stars because

The motion of a particle along a straight line is described by the equation $x = 8 + 12t - t^3$,where $x$ is in $m$ and $t$ is in $s$. The retardation of the particle when its velocity becomes zero is ....... $m s^{-2}$.

If $x > 0, y > 0, z > 0, xy + yz + zx < 1$ and if $\tan^{-1} x + \tan^{-1} y + \tan^{-1} z = \pi$,then $x + y + z$ equals to

Match the following columns regarding the geological time scale of evolution:

Column-$I$	Column-$II$
$A$. $500$ million years ago	$1$. Sea weeds and few plants
$B$. $350$ million years ago	$2$. Jawless fish
$C$. $320$ million years ago	$3$. Invertebrates

The major product of the following reaction is

In the adjoining circuit diagram,the readings of the ammeter and voltmeter are $2 \ A$ and $120 \ V$,respectively. If the value of $R$ is $75 \ \Omega$,then the voltmeter resistance will be $\Omega$.