多选题求平方根方法public static double sqrt (double a)可以传递的参数类型有哪些？（）AbyteBfloatCStringDlong

下列是定义一个接口ITF的程序，在横线处应填入的选项是 ( )public interface ITF{public static final double PI=3.14，public ______ double area(double a，double b)；}

A．interfaee

B．static

C．final

D．abstract

阅读以下函数说明和Java代码，将应填入(n)处的字句写在对应栏内。

【说明】

下面的程序先构造Point类，再顺序构造Ball类。由于在类Ball中不能直接存取类Point中的xCoordinate及yCoordinate属性值，Ball中的toString方法调用Point类中的toStrinS方法输出中心点的值。在MovingBsll类的toString方法中，super.toString调用父类Ball的toString方法输出类Ball中声明的属性值。

【Java代码】

//Point.java文件

public class Point{

private double xCoordinate;

private double yCoordinate；

public Point(){}

public Point(double x,double y){

xCoordinate=x;

yCoordinate=y;

}

public String toStrthg(){

return"("+Double.toString(xCoordinate)+","

+Double.toString(yCoordinate)+")";

}

//other methods

}

//Ball.java文件

public class Ball{

private (1);//中心点

private double radius;//半径

private String color;//颜色

public Ball(){}

public Ball(double xValue, double yValue, double r){

//具有中心点及其半径的构造方法

center=(2);//调用类Point中的构造方法

radius=r;

}

public Ball(double xValue, double yValue, double r, String c){

//具有中心点、半径和颜色的构造方法

(3);//调用3个参数的构造方法

color=c;

}

public String toString(){

return "A ball with center"+center.toString()

+",radius "+Double.toString(radius)+",color"+color;

}

//other methods

}

class MovingBall (4) {

private double speed;

public MovingBall(){}

public MoyingBall(double xValue, double yValue, double r, String c, double s){

(5);//调用父类Ball中具有4个参数的构造方法

speed=s;

}

public String toString(){

return super.toString()+",speed"+Double.toString(speed);

}

//other methods

}

public class test{

public static void main(String args[]){

MovingBall mb=new MovingBall(10,20,40,"green",25);

System.out.println(mb);

}

}

下列是定义一个接口ITF的程序，在横线处应填入的选项是( )。 publid interface ITF { public static final double PI=3.14; public______double area(double a，double B) ; }

A．interface

B．static

C．final

D．abstract

在下列方法的定义中，正确的是 ( )

A．public double x(){．．；return false；}

B．public static int x(double y){．．．}

C．void x(doubled){．．．；return d}

D．public static x(double a){．．}

A.byte

B.float

C.String

D.long

阅读以下说明和Java源程序，将应填入(n)处的字句写在答题纸的对应栏内。

说明

以下程序的功能是计算三角形、矩形和正方形的面积并输出。

程序由5个类组成：AreaTest是主类，类Triangle、Rectangle和Square分别表示三角形、矩形和正方形，抽象类Figure提供了一个计算面积的抽象方法。

程序

public class AreaTest{

public static void main(String args[]){

Figure[]figures={

new Triangle(2,3,3)，new Rectangle(5,8)， new Square(5)

}；

for(int i=0；i＜figures．1ength；i++){

System.out.println(figures[i]+"area="+figures[i]．getArea())；

}

}

}

public abstract class Figure{

public abstract double SetAJea()；

public class Rectangle extends (1) {

double height;

double width;

public Rectangle(double height,double width){

this.height=height;

this.width=width;

}

public String toString(){

return "Rectangle:height="+height+",width="+width+":";

}

public double getArea() { return (2);

} } public class Square extends (3) {

public Square(double width) {

(4);

}

public String toString() {

return "Square:width="+width+":";

} } public class Triangle extends (5). {

double la;

double lb;

double lc;

public Triangle(double la,double lb,double lc) {

this.la=la; this.lb=lb; this.lc=lc;

public String toString(){

return "Triangle: sides="+la+","+lb+","+lc+":";

public double getArea() {

double s=(la+lb+lc)/2.0;

return Math.sqrt(s*(s-la)*(s-lb)*(s?1c))；

}

}

下列程序的执行结果为【 】。

include ＜iostream. h＞

class Point

{

public:

Point(double i, double j) { x=i; y=j;}

double Area() const { return 0.0;}

private:

double x, y;

};

class Rectangle: public Point

{

public:

Rectangle(double i, double j, double k, double 1)

double Area() const {return w * h;}

private:

double w, h;

};

Rectangle: :Rectangle(double i, double j, double k. double 1): Point(i,j).

{

w=k, h=1

}

void fun(Point &s)

{

cout＜＜s. Area()＜＜end1;

}

void main( )

{

Rectangle rec(3.0, 5.2, 15.0. 25.0);

fun(rec)

}

A.public double max(double x,double y)

B.publicintmax(intn,int k)

C.publicintmax(intx,int y, int z)

D.public double max(double n,double k)