A:实行家庭联产承包责任制﹣→推动了中国农业的发展
B:设立深圳等四个经济特区﹣→打开了对外开放的窗口
C:香港、澳门回到了祖国怀抱﹣→标志着祖国统一大业彻底完成
D:1977年底恢复高校入学考试﹣→促进了我国高等教育迅速发展
如图所示,在天花板上的O点系一根细绳,细绳的下端系一小球.将小球拉至细绳处于水平的位置,由静止释放小球,小球从位置A开始沿圆弧下落到悬点的正下方的B点的运动过程中,下面说法正确的是( )
读图和材料,完成下列各题:材料一:我国已探明的矿产资源总值居世界第三位,但人均矿产资源占有量不到世界平均水平的1/2。材料二:我国在矿产资源的开发利用中,乱采乱挖现象比较严重。这种破坏性开采,一方面加快了矿产资源的耗竭速度;另一方面侵占了大片耕地,破坏了植被,引发了生态环境问题。材料三:2007年5月3日,中石油在渤海湾发现储量规模达10亿吨的冀东南堡大油田。是继大庆之后我国发现的第二个十亿吨级的油田。
根据短文内容判断句子正(T)误(F)。Welcome to our school. Our school is on Xianyang Street. It’s next to the Xinhua Library. There is a big garden across from our school. The payphone is between our school and the post office. There are three buildings in our school, the students' building, the teachers'building and a library. The teachers in our school are good. Our school yard is very beautiful. If you come to our school from the airport, take a taxi and go along the highway until you see a bridge. Go across the bridge and turn left. Then go straight along the Bridge Street. Our school is on the right.
①常温下S为固体,而Cl2为气体
②Cl2与H2混合,强光照射剧烈反应,而S与H2反应需较高温度
③与Fe反应,Cl2生成FeCl3,而S生成FeS
④盐酸是强酸,而氢硫酸是弱酸
⑤将Cl2通入氢硫酸中可置换出S.