无差异曲线的形状越接近于直线,该消费者消费的两种商品之间的替代性越大。
参考答案:对
将Na2O2逐渐加入到含有H+、Mg2+、Al3+、NH4+ 的混合液中并微热,产生沉淀和气体的物质的量(mol)与加入的Na2O2物质的量(mol)的关系如图所示,则原溶液中的Mg2+、Al3+、NH4+ 物质的量分别( )
A.2 mol、3 mol、6 mol
B.3 mol、2 mol、6mol
C.2 mol、3 mol、4 mol
D.3 mol、2 mol、2 mol
----Have you got your test result?
----Not yet. The papers _____.
A.are still being corrected
B.are not correcting
C.have already been corrected
D.have not corrected