The oxidation state of $Xe$ in $XeO_3$ and the bond angle in it respectively are:

$A$ body of mass $2 \, kg$ slides down a curved track which is a quadrant of a circle of radius $1 \, m$. All the surfaces are frictionless. If the body starts from rest,its speed at the bottom of the track is ................. $m/s$.

$A$ and $B$ are ideal gases. The molecular weights of $A$ and $B$ are in the ratio of $1: 4$. The pressure of a gas mixture containing equal weights of $A$ and $B$ is $P \ atm$. What is the partial pressure (in $atm$) of $B$ in the mixture?

The value of $\cos 15^{\circ} \cos 7.5^{\circ} \sin 7.5^{\circ}$ is

Water is considered to be polluted if the dissolved oxygen $(D.O.)$ content is less than ... $ppm$ :

The value of $\lambda$ such that $\lambda x^2-10 x y+12 y^2+5 x-16 y-3=0$ represents a pair of straight lines is: