火车通过隧道是指从车头进入隧道到车尾离开隧道，所行的路程正好是车身与隧道长度之和。7t*j(T4y0s
解：
算式：提示:V9e1I1S2}/b5R(v;H,y)l6?+w4h(P7t*j(T4y0s
答：火车通过隧道需9]/T4r9k/s4Q6l*W,k6f分。7t*j(T4y0s