What is the relation between the number density of holes $(n_h)$ and free electrons $(n_e)$ in an intrinsic semiconductor at room temperature?

Donor type impurity is found in

The net charge on an $N-$type semiconductor is

$A$ $P$-type semiconductor is:

In a $P$-type semiconductor, the acceptor energy level $E_A$ is located $57 \, meV$ above the valence band. The maximum wavelength required to create a hole is ....... $\mathring{A}$. (Given: $h = 6.6 \times 10^{-34} \, J \, s$, $c = 3 \times 10^8 \, m/s$, $1 \, eV = 1.6 \times 10^{-19} \, J$)

How is electric conduction produced in an intrinsic semiconductor?