用Na2C204基准物标定KmnO4溶液时,应将溶液加热至75~85℃后,再进行滴定。

用Na2C204基准物标定KmnO4溶液时,应将溶液加热至75~85℃后,再进行滴定。


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阅读如下程序, a = 1: b = 2: plus S, a, b: Print S:不能使其输出结果为3的plus过程为( )。 A、Sub plus(sum, a , b ): sum = a + b: End SubB、Sub plus(ByVal sum , a , b ): sum = a + b: End SubC、Sub plus(sum , ByVal a, ByVal b ): sum = a + b: End SubD、Sub plus(sum , ByRef a , ByRef b ): sum = a + b: End Sub

II型呼吸衰竭合并代谢性酸中毒()。 A、Pa0/sub2/supsubno60mHl.PaCO/sub2/supsubno50mmlgB、Pa0/sub2/supsubno60mHgPaCO/sub2/supsubno45mmgC、Pa0/sub2/supsubno60mmHgPaCO/sub2/supsubno50mmHD、Pa0/sub2/supsubno60mHg、PaCO/sub2/supsubno45mmHgE、Pa0/sub2/supsubno60mHg、PaC0/sub2supsubno45mmHg

以下程序的输出结果是【 】。main(){ int x=0;sub(x,8,1);printf(“%d\n”,x);}sub(int *a,int n,int k){ if(k<=n)sub(a,n/2,2*k);*a+=k;}

在窗体中添加一个名称为Command1的命令按钮,然后编写如下程序: Public x As Integer Private Sub Command1_Click() x=10 Call s1 Call s2 MSgBox x End Sub Private Sub s1() x=x+20 End Sub Private Sub s2() Dim x As Integer x=X+20 End Sub 窗体打开运行后,单击命令按钮,则消息框的输出结果为______。A.10B.30C.40D.50

有如下程序: Private Sub Command1_Click() Dim a As Single Dim b As Single a=5:b=4 Call Sub1(a,b) End Sub Sub Sub1(x As Single,y As Single) t=X X=t\Y Y=t Mod y End Sub 在调用运行上述程序后,a和b的值分别为A.0 0B. 1 1C.2 2D.1 2

A、PH7.38,PaOSUB2/SUB50mmHg,PaCOSUB2/SUB40mmHgB、PH7.30,PaOSUB2/SUB50mmHg,PaCOSUB2/SUB80mmHgC、PH7.40,PaOSUB2/SUB60mmHg,PaCOSUB2/SUB65mmHgD、PH7.35,PaOSUB2/SUB80mmHg,PaCOSUB2/SUB20mmHgE、PH7.25,PaOSUB2/SUB70mmHg,PaCOSUB2/SUB20mmHg血气分析结果符合代偿性代谢性酸中毒( )

以下程序的输出结果是( )。 include main()fint x=0; sub(x,16,2); printf("%d\n", 以下程序的输出结果是( )。include<stdio.h>main()fint x=0;sub(x,16,2);printf("%d\n",x);}sub(int*a,int n,int k){if(k<=n) sub(a,n/2,2*k);*a+=k;}

在窗体中添加一个名称为Commandl的命令按钮,然后编写如下程序:Public X As Integer Private Sub Commandl Click( )x=10 Call slCall s2MsgBox x End Sub Private Sub sl( )x=x+20 End Sub Private Sub s2( )Dim x As Integer x=x+20End Sub窗体打开运行后,单击命令按钮,则消息框的输出结果为( )。A.10B.30C.40D.50

编写如下事件过程: Private sub sub1 (ByVal x1 As String, y1 As String) Dim xt As String Dim i As Integer i = Len(x1) Do While i>= 1 xt = xt + Mid(x1, i, 1) i=i-1 Loop y1 = xt End Sub Private Sub Form. Click() Dim s1 As String, s2 As String s1= "teacher" sub1 s1, s2 Print s2 End Sub 程序运行后,单击窗体,则窗体上显示的内容是A.rehcaetB.tahreeeC.themeeD.eerthea

写出程序运行的结果Public class BasePublic virtual string Hello() {return “Base”;}Public class Sub:BasePublic override string Hello() {return “Sub”;}1. Base b = new Base(); b.Hello;2. Sub s = new Sub(); s.Hello;3. Base b = new Sub (); b.Hello;4. Sub s = new Base(); s.Hello;

有如下程序。 Private Sub Commandl_Click() Dim a As Single Dim b As Single a=5:b=4 Call Sub1 ( a,B)End Sub Sub Subl(x As Single, y As Single) t=x x=t\y y = t Mod y End Sub 在调用运行上述程序后,a和b的值分别为A.0 0B.1 1C.2D.1 2

PaOSUB2/SUB↓,PaCOSUB2/SUB↑提示( )

有如下程序: Private Sub Command1 Click() Dim a As Single Dim b As Single a=5:b=4 Call S(a,B)End Sub Sub S(x As Single,y As Single) t=x x=t\y y=t Mod y End Sub 在调用运行上述程序后,a和b的值分别为A.0 0B.1 1C.2 2D.1 2

运行下列程序:Private Sub form_Click( )x = 8: y = 2Call fun1((x), y)Print x, yEnd SubPrivate Sub fun1(x, y)s = xx = s / yy = s Mod yEnd Sub单击窗体后,则在窗体上显示的结果是( )。A.4 2B.8 2C.8 0D.2 4

在窗体中添加一个命令按钮,编写如下程序: Private Sub Sub1(p,m,n) p=p+1:m=m+1:n=n+1 Print "sub1:";p;m;n End Sub Private Sub Command1_Click() a1=1:b=2:c1=3 Call Sub1(a,b1+3,c1) Print"Main:";a1;b1;c1 End Sub 程序运行后,输出结果为A.Sub: 2 6 4 Main: 2 6 4B.Sub: 2 6 4 Main: 2 6 4C.Sub: 2 6 4 Main: 1 2 3D.Sub: 2 6 4 Main: 2 2 3

class Super {  public int i = 0;  public Super(String text) {  i = 1; }  }  public class Sub extends Super {  public Sub(String text) {  i = 2;  }   public static void main(String args[]) {  Sub sub = new Sub(“Hello”);  System.out.println(sub.i);  }  }  What is the result?()  A、 0B、 1C、 2D、 Compilation fails.

s=”this is the mainstring”,sub=”string”,strindex(s,sub)是()

单选题变直径圆管流,细断面直径d1,粗断面直径d2=2d1,粗细断面雷诺数的关系是( )。ApResub1/sub=0.5Resub2/sub/pBpResub1/sub=Resub2/sub/pCpResub1/sub=1.5Resub2/sub/pDpResub1/sub=2Resub2/sub /p

单选题用HCl滴定NaOH和Na2CO3混合液,首先加入用酚酞指示剂,消耗HCl体积V1,之后用甲基橙指示剂,消耗HCl体积V2,则V1和V2的关系是:A Vsub1/subVsub2 /sub /pB Vsub1/subVsub2/sub /pC Vsub1/sub=Vsub2/sub /pD 不能确定

单选题class Super {  public int i = 0;  public Super(String text) {  i = 1; }  }  public class Sub extends Super {  public Sub(String text) {  i = 2;  }   public static void main(String args[]) {  Sub sub = new Sub(“Hello”);  System.out.println(sub.i);  }  }  What is the result?()A 0B 1C 2D Compilation fails.

单选题煤矿井下的有害气体主要是由()、CO2、H2S、NO2、H2、NH3气体组成。ACOBpCHsub4/sub、SOsub2/sub/pCpSOsub2/sub、CO/pDpCO、CHsub4/sub、SOsub2/sub/p

单选题酶促反应速度(v)达到最大反应速度(Vmax)的80%时,底物浓度[S]为Ap1Ksubm/sub/pBp2Ksubm/sub/pCp3Ksubm/sub/pDp4Ksubm/sub/pEp5Ksubm/sub/p

单选题A pIsub2/sub=Isub3/sub/pB pIsub2/sub=4Isub3/sub/pC pIsub2/sub=2Isub3/sub/pD pIsub3/sub=4Isub2/sub/p

单选题class super (   public int I = 0;   public super (string text) (   I = 1   )   )     public class sub extends super (   public sub (string text) (   i= 2   )   public static void main (straing args) (  sub sub = new sub (“Hello”);   system.out. PrintIn(sub.i);  )   )   What is the result?()A Compilation will fail.B Compilation will succeed and the program will print “0”C Compilation will succeed and the program will print “1”D Compilation will succeed and the program will print “2”

单选题正态分布时,算术平均数、中位数、众数的关系为()Amsub0/sub<msube/sub<(xBmsub0/sub=msube/sub=(xCmsub0/sub>msube/sub>(xDmsube/sub<msub0/sub<(x

多选题下列表示中____的表示形式是正确的。ApUsub95/sub= 1%,vsubeff/sub =9 /pBpUsubr/sub= 1%,k=2 /pCpusubC/sub=0. 5% /pDpusubC/sub=±0 5%.k=1 /p

多选题设up为标准正态分布的p分位数,则有(  )。Ausub0.49/sub>0 Busub0.3/sub<usub0.4 /subCusub0.5/sub=0 Dusub0.23/sub=-usub0.77 /subEusub0.5/sub=-usub0.5/sub

单选题( )被称为广义货币。ApMsub0/sub/pBpMsub1/sub/pCpMsub2/sub/pDpMsub3/sub/p