根据首字母提示,用适当的单词填空,完成短文

根据首字母提示,用适当的单词填空,完成短文Suppose you see a coin on the bottom of a swimming pool and want to dive for it.W_____ do you aim?You should not aim at the coin!When l____ rays go into the water,they bend.The light rays reflected off the coin are bent as they pass t________ the water to your eyes.The b____ of light rays as they pass from one material to a ____ is called refractionRefraction changes the d______ of the rays.The light rays are refracted at an a____ as they pass from the water into the air.This e____ why it is hard for you to locate the coin.So w____you dive in for the coin,you should aim in f____ of it .