The intrinsic semiconductor becomes an insulator at

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 resistance of a semiconductor at $0 \ K$ is:

When the temperature of a silicon sample is increased from $27^\circ C$ to $100^\circ C$,the conductivity of silicon will be

Read the following statements carefully:
$Y:$ The resistivity of a semiconductor decreases with an increase in temperature.
$Z:$ In a conducting solid,the rate of collision between free electrons and ions increases with an increase in temperature.
Select the correct statement from the following:

On heating a semiconductor: