What is the crystalline structure of an intrinsic semiconductor?

When the temperature of a semiconductor is increased,its resistance and electric conductivity respectively.

Which of the following statements is incorrect?

Name the primary constitutional unit of semiconductor composition.

What is the maximum wavelength of electromagnetic radiation that can create an electron-hole pair in a material with a band gap of $0.7 \ eV$? (Planck's constant $h = 4.136 \times 10^{-15} \ eV \cdot s$, velocity of light $c = 3 \times 10^8 \ m/s$).

The conductivity of a semiconductor increases with an increase in temperature because