In the middle of the depletion layer of a reverse-biased $PN$ junction,the

In the case of forward biasing of a $PN-$ junction,which one of the following figures correctly depicts the direction of flow of majority charge carriers?

$A$ semiconductor $(Ge - As)$ has an energy gap of $1.43\, eV.$ What is the maximum wavelength emitted when a hole and an electron recombine in such semiconductor in $\mathring{A}$?

In an unbiased $p-n$ junction:

When a silicon $PN$ junction is in forward biased condition with a series resistance,it has a knee voltage of $0.6\, V$. The current flowing through it is $5\, mA$ when the $PN$ junction is connected to a $2.6\, V$ battery. The value of the series resistance is.....$\Omega$.

In the given options,the diode that is forward biased is