重介质选矿的优点()。
A.分选效率高
B.分选精度高
C.加工费用低
D.所需工人少
参考答案:A, B
下列各组物质中,都是强电解质的是[ ]
A.HBr、HCl、BaSO4
B.NH4Cl、CH3COOH、Na2S
C.NaOH、Ca(OH)2、NH3·H2O
D.HClO、NaF、Ba(OH)2
_____ having some money raises our level of happiness, having too much money does not.
A.While
B.When
C.As
D.Until