Would there be any advantage to adding $n$-type or $p$-type impurities to copper?

If $V_0$ is the volume of a standard unit cell of germanium crystal containing $N_0$ atoms,then the expression for the mass $m$ of a volume $V$ in terms of $V_0, N_0, M$ and $N_A$ is [here,$M$ is the molar mass of germanium and $N_A$ is the Avogadro's constant].

$A$ piece of copper and another of germanium are cooled from room temperature to $77 \ K$. The resistance of

Choose the correct statement.

Carbon,Silicon,and Germanium atoms each have four valence electrons. If their bandgaps are represented by $(E_g)_C$,$(E_g)_{Si}$,and $(E_g)_{Ge}$ respectively,which of the following relations is correct?

Which of the following statements is incorrect?