In the diagram,the input is across the terminals $A$ and $C$ and the output is across the terminals $B$ and $D$. Then the output is

Which of the following is not a Lewis acid?

$A$ particle is released from a height $H$. At a certain height,its kinetic energy is half of its potential energy with reference to the surface of the earth. The height and speed of the particle at that instant are respectively:

$2\,g$ of steam condenses when passed through $40\,g$ of water initially at $25\,^{\circ}C$. The condensation of steam raises the temperature of water to $54.3\,^{\circ}C$. What is the latent heat of steam in $cal/g$?

Vegetative propagation in mint occurs by

If $P_1, P_2, P_3$ are the perimeters of the three circles $x^2+y^2+8x-6y=0$,$4x^2+4y^2-4x-12y-186=0$,and $x^2+y^2-6x+6y-9=0$ respectively,then