How is electric conduction produced in an intrinsic semiconductor?

In a $p$-type semiconductor,the acceptor level is at $50 \text{ meV}$ above the valence band. To produce one hole,the maximum wavelength of the light photon required is (Planck's constant,$h = 6.6 \times 10^{-34} \text{ Js}$ and speed of light in vacuum,$c = 3 \times 10^8 \text{ m/s}$) (in $\mu \text{m}$)

The process of adding impurities to a pure semiconductor is called

Silicon is a semiconductor. If a small amount of $As$ is added to it,then its electrical conductivity . . . . . . .

In a $p$-type semiconductor,which of the following statements is true?

Minority carriers in a $p$-type semiconductor are