The energy band gap (distance between the conduction band and valence band) in a conductor is

GaAs is

The temperature coefficient of resistance of a semiconductor is:

At absolute zero temperature,a semiconductor behaves like

Carbon,Silicon,and Germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by $(E_g)_C$,$(E_g)_{Si}$,and $(E_g)_{Ge}$ respectively. Which one of the following relationships is true in their case?

What is the band gap energy for Germanium $(Ge)$?