![](https://cos-cdn.shuashuati.com/pipixue-wap/2020-1230-1107-56/ti_inject-812ce.png)
阅读和理解下面: class Manager extends Employee{ public Manager(String n,double s,int year,int month,int day){ super(n,s,year,month,day); bonus=0; } public double getSalary(){ double baseSalary-super.gerSalary(); return baseSalary+bonus; } public void setBonus(double b){bonus=b; ) private double bonus; } Manager是Employee的子类,其理由是( )。