When two related populations occupy geographically or spatially separate areas,they are called

If the curves $x^2+p y^2=1$ and $q x^2+y^2=1$ are orthogonal to each other, then

The magnetic field at the centre of a circular current-carrying conductor of radius $r$ is $B_c$. The magnetic field on its axis at a distance $r$ from the centre is $B_a$. The value of $B_c : B_a$ will be:

The coordination number and the oxidation state of the element $E$ in the complex $[E(en)_2(C_2O_4)]NO_2$ (where $en$ is ethylenediamine) are,respectively,

In a seconds pendulum,the mass of the bob is $30\, g$. If it is replaced by a $90\, g$ mass,then its time period will be ... $\sec$.

On heating ammonium dichromate,the gas evolved is