中国药典检查维生素C中的铁盐和铜盐,采用的方法是( )
A.沉淀滴定法B.比色法C.氧化还原滴定法D.紫外分光光度法E.原子吸收分光光度法
参考答案:E
设有如下程序: Prirate Sub Form_Click() Dim a As Integer,b AS Integer a=20:b=50 p1 a,b p2 a,b p3 a,b Print"a=";a,"b=";b End Sub Sub p1(x As Integeh By Val y As Integer) x=x+10 y=y+20 End Sub Sub p2(ByVal x As Integer,y As Integer) x=x+10 y=y+20 End Sub Sub p3 (ByVal x As Integer,ByVal y As Integer) x=x+10 y=y+20 End Sub 该程序运行后,单击窗体,则在窗体上显示的内容是:a= (11) 和b= (12) 。
一般认为,正常的AC/A值应为()
A.2~4
B.4~6
C.6~8
D.8~10
E.随着年龄改变而改变