9. The ADT dictionary does not permit key-null pairs. 10. A key that has no value associated with it does not appear in the dictionary. 11. You cannot traverse a dictionary by both the keys and values in parallel. 12. You can traverse all the keys in a dictionary without traversing the values. 13. You cannot traverse all the values in a dictionary without traversing the keys. 14. A sorted dictionary must use search keys that belong to a class that implements the interface Comparable. 15. The default delimiter for the class Scanner is a white-space character. 16. Duplicate search keys are not permitted in a dictionary that conforms to the Java Class Library Map interface. 17. When using a Scanner object to process text, you can specify any character as a delimiter.