138 CHAPTER 4: ACCESS CONTROL Review Questions 4.12 Given the following class, which of these alternatives are valid ways of referring to the class from outside of the package net.basemaster ? package net.basemaster; public class Base { // ... } Select the two correct answers. (a) (b) (c) (d) (e) 4.13 By simply referring to the class as Base . By simply referring to the class as basemaster.Base . By simply referring to the class as net.basemaster.Base . By importing with net.basemaster.* , and referring to the class as Base . By importing with net.* , and referring to the class as basemaster.Base . Which one of the following class declarations is a valid declaration of a class that cannot be instantiated? Select the one correct answer. (a) class Ghost { abstract void haunt(); }