配制NaOH、KMnO4和Na2S2O3标准溶液均需煮沸这一步骤,某生配制上述溶液的作法如下: (a)量取饱和NaOH溶液于蒸馏水中然后加热煮沸 (b)称取固体KMnO4溶于煮沸冷却的蒸馏水中 (c)称取固体Na2S2O3溶于蒸馏水中煮沸 请指出其错误并加以改正。

配制NaOH、KMnO4和Na2S2O3标准溶液均需煮沸这一步骤,某生配制上述溶液的作法如下: (a)量取饱和NaOH溶液于蒸馏水中然后加热煮沸 (b)称取固体KMnO4溶于煮沸冷却的蒸馏水中 (c)称取固体Na2S2O3溶于蒸馏水中煮沸 请指出其错误并加以改正。


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单选题class super {  public int getLength()  {return 4;}  }  public class Sub extends Super {  public long getLength() {return 5;}  public static void main (String[]args)  {  super sooper = new Super ();  Sub sub = new Sub();  System.out.printIn(  sooper.getLength()+ “,” + sub.getLength()   };  }  What is the output?()A 4, 4B 4, 5C 5, 4D 5, 5E The code will not compile.

单选题class Super { public int getLenght() { return 4; } } public class Sub extends Super { public long getLenght() { return 5; } public static void main(String[] args) {Super sooper = new Super(); Sub sub = new Sub(); System.out.println( sooper.getLenght() + “,” + sub.getLenght() ); } } What is the output? ()A 4,4B 4,5C 5,4D 5,5E Compilation fails.

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1. class Super {  2. private int a;  3. protected Super(int a) { this.a = a; }  4. }  .....  11. class Sub extends Super {  12. public Sub(int a) { super(a); }  13. public Sub() { this.a= 5; }  14. }  Which two, independently, will allow Sub to compile?()AChange line 2 to: public int a;BChange line 2 to: protected int a;CChange line 13 to: public Sub() { this(5); }DChange line 13 to: public Sub() { super(5); }EChange line 13 to: public Sub() { super(a); }

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