接口的相关问题，求解答

//接口：从微观上讲，接口板代表一种能力或约定

interface Study{
int i = 1;
int b= 2;
void fire();
}

interface Travel{
int q= 1;
int w =2;
void fly();
}
interface Run{
int e=1;
int r=4;
void walk();

}

abstract class Person{

}
class Student extends Person implements Study,Travel,Run{
String name;
public Student(String name) {

    this.name = name;
}
public void eat() {
    System.out.println(name+"很能吃");
}
@Override   //因为接口的抽象方法是public权限，所以实现重写方法 的权限也必须是public
public void fire() {
    System.out.println(name+"在喷火");
}

@Override
public void fly() {
    System.out.println(name+"在飞天");
}
@Override
public void walk() {
    // TODO Auto-generated method stub
    System.out.println(name+"在飞");
    
}

}
public class Test {

public static void main(String[] args) {

    Study study = new Student("小明");
            study.fire();
    Travel travel = new Student("小红");
            travel.fly();