What value should headPtr contain if there are no nodes for it to point to?

You have forgotten your password, so you click on "forgot my password" to have a new password sent by email. Sometimes the site tells you what your password was; other times, it sends you a new (usually temporary) password. What are the privacy implications of each approach?

What will be an ideal response?

Answer the following statements true (T) or false (F)

1) An abstract class may be derived from another abstract class. 2) Objects of abstract base classes can be instantiated. 3) An abstract class cannot have instance data and non-abstract methods. 4) Attempting to instantiate an object of an abstract class is a logic error.