6) If your class does not include a customized tostring () method: a). You cannot use strings in your class You would see: ObjectTypeeMemoryLocation when used You cannot print your objects b) You use the tostring( implementation of the Object class c) d) e) You need to use super.tostring ) 7) The list interface can be instantiated through the following abstract classes: a) Deque b) ArrayList c) HashMap d) LinkedList e) It is not possible An abstract data type ADT is: a) 8) Something very hard to understand b) An encapsulated set of data and function members c) A programmer defined type enclosing state and behaviour d) A user defined type enclosing state and behaviour e) A class that requires no contract 9) Both ArrayLists and LinkedLists are: a) Sequential data structures b) Stored in consecutive memory positions c) Part of the collections interface d) Linked with lines and arrows e) Abstract classes 10) A map can be instantiated via a) HashMap b) LinkedHashSet c) TreeSet d) MapList e) None of the above