You are the network consultant from passguide.com. You have been asked for which two features of optical networks allow data to be transmitted over extremely long distances? （） ["Encryption","Bandwidth limits","Minimal signal loss","No EMI"]
拱坝坝身泄水的方式有（） ["自由跌流式","鼻坎挑流式","滑雪道式","底流消能式"]
二战中欧洲战场的转折是（）。 ["中途岛海战","斯大林格勒战役","阿拉曼战役","诺曼底登陆"]
测试足部感觉包括：（） ["振动感","痛觉","温度觉","触觉","压力觉"]
重力坝地基处理时，进行帷幕灌浆和固结灌浆的作用是什么？
相对于水利枢纽工程建设，水库调度的（）很少，但可以获得可观的（）。
