英语翻译A point source of light is placed in a liquid.Light rays
英语翻译 A point source of light is placed in a liquid.Light rays from the source leave the liquid surface through a circular area of radius 10 cm .The refractive index of the liquid is 1.3.The depth of the source below the liquid surface is? A.5.7cm B.8.3cm C10cm D.20cm