When a person dies after being stung by a bee followed by the administration of penicillin,death may be due to:

$A$ 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:

The maximum value of $ \left(\frac{1}{x}\right)^{x} $ is

If a body is projected with an angle $\theta$ to the horizontal,then

In a compound microscope,the focal length of the objective lens is $1.2 \ cm$ and the focal length of the eyepiece is $3.0 \ cm$. When the object is kept at $1.25 \ cm$ in front of the objective,the final image is formed at infinity. The magnifying power of the compound microscope is:

Identify the correct decreasing order of the following with respect to altitude from the atmosphere:
$I$. Troposphere
$II$. Mesosphere
$III$. Thermosphere