题目

Everyone agrees that it’s necessary to reduce carbon emissions （排放物） around the world. There is less agreement over exactly how nations should go about achieving a more carbon - free planet. Thus, the environmental equivalent: cap – and – trade carbon emissions, or place a carbon tax on all users? With cap – and – trade programs, governments limit the level of carbon produced by an industry. Companies that hold their emissions below the cap can sell their remaining allowance on a carbon market, while companies that go beyond their limit must purchase credits on that m下列有关实验操作、现象及结论的叙述正确的是A．用钠可以检验某无水酒精中是否含有水B．除去甲烷中混有的少量乙烯,可以将混合气体通过酸性KMnO4溶液C．制取乙酸乙酯时,试剂加入的顺序是：先加入乙醇，后慢慢加入浓硫酸，最后加入乙酸D．在蔗糖溶液中加入少量稀硫酸，水浴加热后，再加入少量新制的氢氧化铜悬浊液,加热至沸腾,没有砖红色沉淀生成,说明蔗糖没有水解