Given classes defined in two different files： 
1. package util； 
2. public class BitUtils { 
3. public static void process（byte[]） { /* more code here */ } 
4. } 
1. package app； 
2. public class SomeApp { 
3. public static void main（String[] args） { 
4. byte[] bytes = new byte[256]； 
5. // insert code here 
6. } 
7. } 
What is required at line 5 in class SomeApp to use the process method of BitUtils？（） 

34. HashMap props = new HashMap（）； 
35. props.put（”key45”， “some value”）； 
36. props.put（”key12”， “some other value”）； 
37. props.put（”key39”， “yet another value”）； 
38. Set s = props.keySet（）； 
39. // insert code here 
What， inserted at line 39， will sort the keys in the props HashMap？（）