请各位帮忙看一下这个题目

Question

Answer 1

public class Student {
private String name, xuehao;
private int chengji;

public Student(String name, String xuehao, int chengji) {
    this.name = name;
    this.xuehao = xuehao;
    this.chengji = chengji;
}

public String 计算学生成绩方法() {
    String cj = null;
    if(chengji >= 90) {
        cj = "A";
    } else if(chengji >= 80) {
        cj = "B";
    } else if(chengji >= 70) {
        cj = "C";
    } else if(chengji >= 60) {
        cj = "D";
    } else {
        cj = "E";
    }
    return "姓名：" + name + "，学号：" + xuehao + "，成绩：" + cj;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getXuehao() {
    return xuehao;
}

public void setXuehao(String xuehao) {
    this.xuehao = xuehao;
}

public int getChengji() {
    return chengji;
}

public void setChengji(int chengji) {
    this.chengji = chengji;
}

}

public class Students {
private Student[] students = new Student[100];
private static int amount;

public Students(int amount) {
    Students.amount = amount;
}

public int avergeScore() {
    int sum = 0;
    for (Student student : students) {
        sum += student.getChengji();
    }
    return sum / amount;
}

public int highestScore() {
    int max = 0, chengji = 0;
    for (Student student : students) {
        chengji = student.getChengji();
        if(chengji > max) {
            max = chengji;
        }
    }
    return max;
}

public void newStudent(Student student) {
    students[students.length] = student;
}

}