The complex formed by a pair of synapsed homologous chromosomes is called:

$A$ particle is projected from a point at an angle $\theta$ with the horizontal direction. At any time $t$,if $p$ is the linear momentum,$y$ is the vertical displacement,and $x$ is the horizontal displacement,which of the following graphs does $NOT$ represent the variation of kinetic energy $(KE)$ of the particle?

Which of the following is an incorrect pair?

If the harmonic mean between the roots of $(5+\sqrt{2}) x^2-b x+(8+2 \sqrt{5})=0$ is $4$,then the value of $b$ is

If a line $l$ passes through $(k, 2k), (3k, 3k)$ and $(3, 1)$ where $k \neq 0$,then the distance from the origin to the line $l$ is

When $H_2SO_4$ reacts with $PCl_5$,the obtained product is/are: