题目

某中学学生到离校的地方去春游，先谴队与大队同时出发，其行进速度是大队的倍，以便提前半小时到达目的地做准备工作，求先遣队与大队的速度各是多少？若设大队的速度为，则可列方程为                   ．    答案： Have you ever seen people building houses? To build a house , you need workers. They use their hands , tools(工具) and machines to put things together. Building the ISS（国际太空站） is the same. The difference is that the workers are astronauts. They walk in space and use robots’ arms and hands to do their work.In the space station ,astronauts are comfortable. The temperature there is about 21℃.But outside the station , it can be too hot or cold for people. In the sunlight, it’s about 120℃. In the shadow(阴暗处)of the station, it’s about -85℃ . So when astronauts walk in space , they have to wear heavy clothes----spacesuits.Spacesuits also keep astronauts safe from flying rubbish(垃圾)in space.Each time people go into space , they leave rubbish there. So astronauts should be careful because there’s a lot of rubbish, some rubbish goes many times as fast as a plane !Space walking is not easy , and it can be dangerous. So getting ready for it takes a lot of time to learn. Astronauts will need to do 160 space walks to finish their work in the ISS. That will take about 1,900man-hour of work1.What’s the temperature in the space station?A.21℃B.120℃C.-85℃D.-21℃2.The astronauts work in space with______.A.scientists’ handsB.tools in their handsC.robots’ arms and handsD.workers’ hands3.Which of following is TRUE according to the passage?A.Space walking is very comfortableB.Space walking is difficultC.Astronauts needn’t wear spacesuits when walking in spaceD.Space walking is very safe4.What does the underlined word“spacesuit”mean in Chinese?A.太空服B.防暴服C.羽绒服D.雨衣5.Which of following is not TRUE according to the passage?A.Spacesuits can keep astronauts warmB.Spacesuits can keep astronauts safeC.Flying rubbish in space goes very slowlyD.Outside the station ,it can be too cold or hot for people