// Exa 3.21.9 clc; clear; close; // Given data n_i = 10^16;// in /m3 N_D = 10^22;// in /m^3 n = N_D;// in /m^3 disp(n,"Electron concentration per m^3 is"); p = (n_i)^2/n;// in /m^3 disp(p,"Hole concentration per m^3 is");