根据对话内容从方框中选择能填入空白处的最佳选项补全对话，其中有两项多余。
A：What good weather!
B：Yeah!____
A：Let's go out for a tour．
B：Good idea．____
A：No.But I visited a beautiful place last weekend．
B：____
A：It's near our city．
B：The New Farm?
A：Yes．____
B：Of course．But it was in winter．
A：The New Farm is beautiful in spring．____
B：OK．
A．It's raining again． B．Where is it? C．I like warm weather． D．Did you visit the city? E．Let's go there again． F．Do you often take a tour at weekends? G．Did you visit it? |
，外层材料的折射率为
。若光在真空中传播速度为
，则对于光由它的一端射入经多次全反射后从另一端射出的过程中，下列判断中正确的是
