In which figure,the junction diode is forward biased?

Show the direction of the electric field that arises in a $p-n$ junction.

For the forward biased diode characteristics shown in the figure,the dynamic resistance at $I_{D} = 3 \, \text{mA}$ will be $..... \, \Omega$.

In a semiconductor $p-n$ diode, the doping concentrations on $p$-side and $n$-side are $10^{15} \text{ atoms/cm}^3$ and $10^{18} \text{ atoms/cm}^3$, respectively. Which one of the following statements is true?

An electron in the $n$-region of a $p-n$ junction moves towards the junction with a speed of $5 \times 10^5 \ m/s$. If the barrier potential of the junction is $0.45 \ V$, then the speed with which the electron enters the $p$-region after penetration through the barrier is (Charge of the electron $e = 1.6 \times 10^{-19} \ C$ and mass of the electron $m = 9 \times 10^{-31} \ kg$).

To make a $PN$ junction conducting,