[填空题]
At what angle should the axes of two Polar*zfd.w)x8s 4mdd;.suy rv4u loids be placed snwg+x(b, )vyng,hf l/o as to reduce the intensity of the incident unpolarized lighxh ),,/l by(+gnvfwn gt to
(a) $\frac{1}{3}$ , $^{\circ}\,$
(b) $\frac{1}{10}$ ? $^{\circ}\,$
