现代建筑的门窗框架常用电镀加工成的古铜色硬铝制造.取硬铝样品进行如图所示的实验(每一步试剂均过量),由此可推知,硬铝的组成为( )
A:Al、Cu、Mg、Si
B:Al、Mg、Si、Zn
C:Al、Fe、C、Cu
D:Al、Si、Zn、Na
下列实例中,利用物体惯性的是( )
—I will visit my grandparents in Beijing next month. Could you please tell me______?
—Oh, you may take the subway there.