Which of the following energy band diagrams shows the $N$-type semiconductor?

$A$ pure semiconductor crystal has $8 \times 10^{28} \text{ atoms/m}^3$. It is doped with a $2 \text{ ppm}$ concentration of pentavalent atoms. The number of holes formed in the semiconductor crystal is (Intrinsic carrier concentration,$n_i = 1 \times 10^{16} \text{ m}^{-3}$).

In an $n-$type semiconductor,which of the following statements is true?

Which of the following statements is correct regarding the charge of semiconductors?

To obtain a $P$-type germanium semiconductor,it must be doped with

In a $P$-type semiconductor,the acceptor energy levels $E_A$ are located: