We find that 20% of the original intensity of a beam of photons is transmitted from air through a 1-cm-thick material having a dielectric constant of 2.3 and back into air. 

Determine the fraction of the beam that is 

(a) Reflected at the front surface;
(b) Absorbed in the material; and
(c) Reflected at the back surface.
Determine the linear absorption coefficient of the material.