The histogens are classified on the basis of

If the equation $x^2+2 \sqrt{2} xy+2y^2+4x+4 \sqrt{2}y+1=0$ represents a pair of parallel straight lines,find the distance between them.

Two charges $q_1$ and $q_2$ are placed $30\,cm$ apart,as shown in the figure. $A$ third charge $q_3$ is moved along the arc of a circle of radius $40\,cm$ from $C$ to $D$. The change in the potential energy of the system is $\frac{q_3}{4\pi \epsilon_0}k$,where $k$ is:

The network shown in the figure is part of a complete circuit. If at a certain instant,the current $I$ is $5 \ A$ and it is decreasing at a rate of $10^3 \ A \ s^{-1}$,and if $I$ is reversed in direction,then $V_B - V_A$ equals .......... $V$.

If $x + \sqrt{x^2 + 1} = a$,then $x =$

What is the foundation of any breeding program?