1. 编写一个java程序，包含一个父类Telephone和一个子类Mobilephone，父类中的属性包括电话品牌、电话号码、通话时间、费率，子类中的属性包括父类中的所有属性和网络类型、被叫时间。同时对两者都计算出话费。（验证性实验）

2. 创建一个Student抽象类，包含学生的姓名、所学课程、课程成绩等属性；创建Student的两个子类Undergraduate类和Postgraduate类。（设计性实验）-1 to write a java program, including a parent Telephone and a subclass Mobilephone, parent class attributes include phone brand, phone number, call duration, rates, subclass attributes include all attributes in the parent class and networks type, called time. At the same time both the calculated charges. (Confirmatory test)

(2) Create a Student abstract class that contains the student s name, course, course grades and other school property　created two subclasses Undergraduate Student classes and Postgraduate classes. (Design of experiments)