题型:名词解释 —Have you finished your homework? —Not _____. There are still some exercises to be done.A. already B. yet C. just D. ever 查看答案
题型:名词解释 计算题:已知条件:a)上图中道岔均为12#,线间距均为5m,连接曲线半径R=400m,正线通过超限列车,设高柱信号机,1,3道不通行超限列车设矮柱信号b)道岔配列两岔心距离为LN=43mc)警冲标至岔心距离L警=50md)信号机至岔心距离高柱 L信=71m矮柱 L信=57m如Ⅱ道下行有效长为850m,试求其余各道上下行有效长。 查看答案