To make a beautiful campus, please ____ ____that rubbish is thrown into dustbins.
如图所示为一直角棱镜的横截面,∠bac=900,∠abc=600,一平行细光束从O点沿垂直于bc面的方向射人棱镜,已知若不考虑原入射光在bc面上的反射光,则下列说法中正确的是 ( )