Identify the incorrect pair from the following.

$A$ candle placed $25 \ cm$ from a lens forms an image on a screen placed $75 \ cm$ on the other side of the lens. The focal length and type of the lens are:

An ideal gas of mass $m$ in a state $A$ goes to another state $B$ via three different processes as shown in the figure. If ${Q_1}, {Q_2}$ and ${Q_3}$ denote the heat absorbed by the gas along the three paths,then

Diffraction effects are easier to notice in the case of sound waves than in the case of light waves because

The resultant gate and its Boolean expression for the given circuit is

The solution of $\frac{dy}{dx} + y = e^x$ is