1、 创建一个对象数组，数组的元素是学生对象，学生的信息包括学号、姓名和成绩(一门课成绩)，求其总人数和平均分。（学生对象不得少于5个）

以下是一个示例代码，创建了5个学生对象，并计算了总人数和平均分：

class Student {
    int id;
    String name;
    double score;

    public Student(int id, String name, double score) {
        this.id = id;
        this.name = name;
        this.score = score;
    }
}

public class Main {
    public static void main(String[] args) {
        Student[] students = new Student[5];
        students[0] = new Student(1, "张三", 90);
        students[1] = new Student(2, "李四", 80);
        students[2] = new Student(3, "王五", 70);
        students[3] = new Student(4, "赵六", 85);
        students[4] = new Student(5, "钱七", 95);

        int count = students.length;
        double sum = 0;
        for (int i = 0; i < count; i++) {
            sum += students[i].score;
        }
        double average = sum / count;

        System.out.println("总人数：" + count);
        System.out.println("平均分：" + average);
    }
}

输出结果为：

总人数：5
平均分：84.0