[填空题]
Two polarizers are orjamx725 e(zim9qvcphd( -vb, i 1,jcu hg22in /tu-xmlented at 40$^{\circ}\,$ to each other and plane-polarized light is incident on them. If only 15% of the light gets through both of them, what was the initial polarization direction of the incident light? $^{\circ}\,$
