N-type Si, GaAs, and 4H SiC are all doped to the level of ND=10^17cm^-3. Determine the volumes of each of these semiconductors that will on avg contain one hole. The intrinsic carrier concentrations are ni=1.02*10^10 cm^-3,ni= 2.1*10^ cm^-3, and 10^-7 cm^-3.