Which stage of prophase-$I$ is represented in the given figure?

Which one of the following is a stimulant?

$A$ line segment $AM = a$ moves in the $XOY$ plane such that $AM$ is parallel to the $X$-axis. If $A$ moves along the circle $x^2 + y^2 = a^2$,then the locus of $M$ is

If both the mass and the radius of the earth decrease by $1\%$,the value of the acceleration due to gravity will

Sensitivity of a potentiometer can be increased by

Two finite sets have $m$ and $n$ elements. The total number of subsets of the first set is $56$ more than the total number of subsets of the second set. The values of $m$ and $n$ are