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

1) All virtual functions in an abstract base class must be declared as pure virtual functions
2) Referring to a derived-class object with a base-class handle is dangerous.
3) A class is made abstract by declaring that class virtual.
4) If a base class declares a pure virtual function, a derived class must implement that
function to become a concrete class.
5) Polymorphic programming can eliminate the need for switch logic.

1.False. An abstract base class can include virtual functions with implementations.
2.False. Referring to a base-class object with a derived-class handle is dangerous.
3.False. Classes are never declared virtual. Rather, a class is made abstract by including at least one pure virtual function in the class.
4.True.
5.True.