选择题:Traffic accidents killed more than 104,000 people

题目内容:
Traffic accidents killed more than 104,000 people in China last year. Chinese cities have more cars than before. Every day many people are ___1___ while they cross the road. Most of ___2___ are old people and children. Old people are often killed because they usually can.t see clearly or hear very well. ___3___ are killed because they are careless. A car, truck or bus can.t stop very quickly if it is going very fast. The faster a car is traveling, the longer it takes to stop. But people walking in the street do not always understand this. It.s ___4___ for people to know how fast a car is traveling. The new traffic laws were put into use ___5___ May 1st, 2004. The new traffic laws will make the streets safer for walking and driving. 第一空
参考答案:

4、图示槽形截面铸铁梁,F=10 kN,Me=70 kN·m,许用拉应力[σt]=35 MPa,许用

4、图示槽形截面铸铁梁,F=10 kN,Me=70 kN·m,许用拉应力[σt]=35 MPa,许用压应力[σc]=120MPa。试校核梁的强度。(20分)

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