The following are positioned in sequence: a source of beam of natural light intensity i0; three ideal polarizers a, b, c; and an observer. polarizer axis angles are measured clockwise from the vertical, from the perspective of the observer. the axis of polarizer a is set a zero degrees (vertical), and the axis angle of polarizer c is set at 50 degrees.

a) if polarizer b is set so the beam intesity is zero at the observer, what are the two possible axis angle settings of polarizer b?

b) if polarizer b is set so that the beam intensity at the observer is a maximum, what is the axis angle of the polarizer b? show detailed steps

c) if the axis angle of polarizer b is set to 120degrees, what is the ratio of the intensity of the beam at the observer to the intensity of the source?