Which are valid identifiers？（）  

Which method implementations will write the given string to a file named "file"， using UTF8 encoding？（）  
IMPLEMENTATION a： 
 public void write（String msg） throws IOException {  
FileWriter fw = new FileWriter（new File（"file"））；  
fw.write（msg）；  
fw.close（）；  
}  
IMPLEMENTATION b： 
 public void write（String msg） throws IOException { 
 OutputStreamWriter osw =  new OutputStreamWriter（new FileOutputStream（"file"）， "UTF8"）；  osw.write（msg）；  
osw.close（）；  
}  
IMPLEMENTATION c：  
public void write（String msg） throws IOException {  FileWriter fw = new FileWriter（new File（"file"））；  
fw.setEncoding（"UTF8"）；  
fw.write（msg）；  
fw.close（）；  }  
IMPLEMENTATION d：  
public void write（String msg） throws IOException {  FilterWriter fw = FilterWriter（new FileWriter（"file"）， "UTF8"）；  
fw.write（msg）；  fw.close（）；  
}  
IMPLEMENTATION e：  
public void write（String msg） throws IOException {  
OutputStreamWriter osw = new OutputStreamWriter（  new OutputStream（new File（"file"））， "UTF8"  ）；  
osw.write（msg）；  
osw.close（）；  
}  

Given the following code， which code fragments， when inserted at the indicated location， will succeed in making the program display a button spanning the whole window area？（）  
import java.awt.*； 
 public class Q1e65 {  
public static void main（String args[]） {  
Window win = new Frame（）；  
Button but = new Button（"button"）；  
// insert code fragment here  win.setSize（200， 200）； 
 win.setVisible（true）； 
 }  
}