题型:问答题 简答题 改错题.Every one year, thousands of people visit the city Venice. It's very beautiful. There are not any read there, so there are not any cars, buses and taxis either. There are canals only. All of them add to 178 and one of them is quite big while rest are small. People move up and down the canals with boats. Venice is sink now. It is going down. It was said that in 2040 Venice might be under water. The sea calling Adriatic(亚得里亚海)will cover it.1.______2.______3.______4.______5.______6.______7.______8.______9.______ 10.______ 查看答案
题型:问答题 简答题 (10分)如图,水平面上O点右侧空间有一匀强电场,场强大小E =,方向水平向右,在O处放一个质量为m=0.1kg、带电量的绝缘物块,它与水平面之间的动摩擦因数μ=0.2。现给物块一个水平向右的初速度,(已知物块与水平面间的最大静摩擦力等于其滑动摩擦力,g取10m/s2)求:(1)物块第一次速度为零时,该点与O点电势差的大小(2)物块最终停止时,该点与O点的水平距离。 查看答案
题型:问答题 简答题 (1)暴雨倾盆 (2)紧急动员 (3)战胜洪水 (4)冲垮大堤 (5)抗灾抢险 正确选项为( )A.1—2—4—3—5B.1—4—2—5—3C.5—3—4—2—1D.4—1—2—3—5 查看答案