创建如下三个类：（People类中的三个方法分别输出一些信息，ChinaPeople 和AmericanPeople类重写父类的三个方法）。

package zhongqiuzuoye;

public class People {
    protected double height;
    protected double weight;
    public double getHeight() {
        return height;
    }
    public void setHeight(double height) {
        this.height = height;
    }
    public double getWeight() {
        return weight;
    }
    public void setWeight(double weight) {
        this.weight = weight;
    }

    public void speakHello()
    {
    }
    public void averageHeight()
    {
    }
    public void averageWeight()
    {
    }

}

package zhongqiuzuoye;

public class ChinaPeople extends People{
    public void chinaGoufu()
    {
        System.out.println("坐如钟，站如松");
    }
    public void speakHello()
    {
        System.out.println("你好");
    }
    public void averageHeight()
    {
        System.out.println("中国人平均身高为170cm");
    }
    public void averageWeight()
    {
        System.out.println("中国人平均体重是70kg");
    }

}

package zhongqiuzuoye;

public class AmericnPeople extends People{
    public void chinaGoufu()
    {
        System.out.println("直拳");
    }
    public void speakHello()
    {
        System.out.println("hello");
    }
    public void averageHeight()
    {
        System.out.println("美国人平均身高为180cm");
    }
    public void averageWeight()
    {
        System.out.println("美国人平均体重是80kg");
    }

}

package zhongqiuzuoye;

public class TestPeople {

    public static void main(String[] args) {

        ChinaPeople c =new ChinaPeople();
        c.speakHello();
        c.averageHeight();
        c.averageWeight();

        AmericnPeople a=new AmericnPeople();
        a.speakHello();
        a.averageHeight();
        a.averageWeight();

}
}