For an intrinsic semiconductor at temperature $$T=0K$$, which of the following statement is true?

For a MOS capacitor, $$\mathrm{V_{fb}}$$ and $$\mathrm{V_{t}}$$ are the flat-band voltage and the threshold voltage, respectively. The variation of the depletion width ($$\mathrm{W_{dep}}$$) for varying gate voltage ($$\mathrm{V_{g}}$$) is best represented by

In an extrinsic semiconductor, the hole concentration is given to be 1.5$$n_i$$ where $$n_i$$ is the intrinsic carrier concentration of 1 $$\times$$ 10$$^{10}$$ $$cm^{-3}$$. The ratio of electron to hole mobility for equal hole and electron drift current is given as ___________ (rounded off to two decimal places).

In a semiconductor device, the Fermi-energy level is 0.35 eV above the valence band energy. The effective density of states in the valence band at T = 300 K is 1 $$\times$$ 10$$^{19}$$ cm$$^{-3}$$. The thermal equilibrium hole concentration in silicon at 400 K is _____________ $$\times$$ 10$$^{13}$$ cm$$^{-3}$$ (rounded off to two decimal places).

Given kT at 300 K is 0.026 eV.