Q149. Which class is the immediate superclass of the Container class?
Component

Q150. If a method is declared as protected, where may the method be accessed?
A protected method may only be accessed by classes or interfaces of the same package or by subclasses of the class in which it is declared.

Q151. How can the Checkbox class be used to create a radio button?
By associating Checkbox objects with a CheckboxGroup.

Q152. Which non-Unicode letter characters may be used as the first character of an identifier?
The non-Unicode letter characters $ and _ may appear as the first character of an identifier