我国外交成就按时间先后排序，正确的是（    ）

①周恩来出席万隆会议，促进中国与亚非各国的团结与合作

②中美两国关系开始走向正常化

③中国在联合国安理会常任理事国的合法席位得到恢复

④中国加入世贸组织

一袋方便面2元8角，也可以写作2.80元.

    This is a s____  of twin brothers, Justin and Paul. Their friend Susan calls them for h____ . Justin and Paul drive to Hill Building q____ . Three man in police uniform p____  them into a green van. They are not p____ . They are the robbers. The twin brothers aren't a____ . Paul opens the back door of the van w____  a knife. They take different r____  to the police station. They meet the robbers a____  in the police station. They are s____ . The policemen stop the van because the back door of the van is open.

    （1）﹣$\sqrt{4}$÷|﹣2$\sqrt{2}$×sin45°|+（﹣$\frac{1}{2}$）^﹣1÷（﹣1⁴×$\frac{1}{2}$）

                        （2）先化简（$\frac{2}{x+2}$+$\frac{x+5}{x^2+4x+4}$）×$\frac{x+2}{x^2+3x}$，然后选择一个你喜欢的数代入求值．

我国在南极洲建立科学考察站一般都选择在（  ）