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5、下面的代码使用__interrupt关键字定义了一个中断服务子程序(ISR),请找出这段代码的错误之处。 __interrupt double compute_area(double radius) { double area=PI*radius*radius; printf("nArea=%f",area); return area; }


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更多 “5、下面的代码使用__interrupt关键字定义了一个中断服务子程序(ISR),请找出这段代码的错误之处。 __interrupt double compute_area(double radius) { double area=PI*radius*radius; printf("nArea=%f",area); return area; }” 相关考题
考题 阅读下列程序说明和C代码,把应填入其中n处的字句写在对应栏内。【说明】下面的程序能够计算不同图形的面积。程序中把每个图形的数据定义成结构类型,利用共同体类型描述2种图形的数据。程序根据输入参数代表的图形类型,求出图形的面积并输出。【程序】struct Circle{float x,y; /*圆心位置*/float r; /*圆半径*/};struct Rectangle{float width; /*矩形宽*/float length; /*矩形长*/};union shape{struct Circle circle;/*圆数据结构*/struct Rectangle rectangle;/*矩形数据结构*/};main(){union shape a;float area;int i;printf(“input number: 1circle,2rectangle,3 end\n”);scanf("%d",i);while (1) /*循环接收输入,并计算输出*/{switch(i){case 1:printf(“input radius:\n”);scanf(“%f”, (2);/*共同体类型变量接收输入*/area=3.1415926* (3);printf(“the area of circle=%f\n”,area);break;case 2:printf(“input width and length :\n”);seanf(“%f,%f”, (4);/*共同体类型变量接收输入*/。area=(5);printf(“the area of rectangle=%f\n”,area);break;}printf(“input number:1 circle,2 rectangle,3 end\n”);scanf(“%d”,i);}}

考题 阅读以下说明和Java程序,将应填入(n)处的字句写在对应栏内[说明]以下程序的功能时三角形、矩形和正方形的面积输出。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。[Java程序]public class areatest {public static viod main(string args[]){Figure[]Figures={New triangle(2,3,3),new rectangle(5,8),new square(5)};for(int i=0; i<Figures.length;i++){system.out.println(Figures+"area="+Figures.getarea());}}}public abstract class figure {public abstract double getarea();}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 exends (3){public square(double width){(4);}public string tostring(){return"square:width="+width":";}}public class triangle entends (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 get area(){double s=(la+lb+lc)/2.0;return math.sqrt(s*(s-la)*(s-lb)*(s-lc));}}

考题 阅读下列Java程序和程序说明,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toString方法输出中心点的值。在MovingBall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。public class Point{private double xCoordinate;private double yCoordinate;public Point 0 }public Point(ouble x, double y){xCoordinate = x;yCoordinate = y;}public String toString(){return "( + Double.toString(Coordinate)+ ","+ Double.toString(Coordinate) + ");}//other methods}public class Ball{(1); //中心点private double radius; //半径private String colour; ///颜色public Ball() { }public Ball(double xValue, double yValue, double r)// 具有中心点及半径的构造方法{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、半径及颜色的构造方法{(3);//调用3个参数的构造方法colour = c;}public String toString(){return "A ball with center" + center, toString() + ", radius"+ Double.toString(radius) + ", colour" + colour;}//other methods}public class MovingBall. (4){private double speed;public MovingBall() { }public MovingBall(double xValue, double yValue, double r, String e, 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 Tester{public static void main(String args[]){MovingBall mb = new MovingBall(10,20,40,"green",25);System.out.println(mb);}}

考题 ●试题六阅读下列程序说明和C++代码,将应填入(n)处的字句写在答卷的对应栏内。【说明】源程序中定义了Circle类与Money类,Circle类可对半径为r的圆进行周长与面积的计算,而Money类用于计算一圆形游泳池的造价。游泳池四周有原形过道,过道外围上栅栏,过道宽度为3米,根据键入的游泳池半径,每米栅栏价格及每平方米过道价格,即可计算出游泳池的造价。请按要求完成下列操作,将程序补充完整。①定义符号常量PI(值为3.14159f)与WIDTH(值为3.00f),分别用于表示圆周率与过道的固定宽度。②定义Circle类默认构造函数,把私有成员radius初始化为参数r的值。③完成Money类默认构造函数的定义,把私有成员FencePrice(每米栅栏的价格)、 ConcretePrice(每平方米过道的价格)初始化为参数f,c的值。④完成Money类成员函数float Money::TotalMoney(float fencelen, float conarea)的定义,根据参数fencelen(栅栏的长度)和conarea(过道的面积),返回栅栏与过道的总造价。注意:除在指定位置添加语句之外,请不要改动程序中的其他内容。源程序文件test4.cpp清单如下:#include iostream.h(1)class Circle{private:float radius;public:(2)float Circumference(){return 2 * PI * radius;}float Area(){return PI * radius * radius;}};class Money{private:float FencePrice;float ConcretePrice;public:Money(float f,float c);float TotalMoney(float fencelen, float conarea);};Money::Money(float f,float c){(3)}float Money::TotalMoney(float fencelen, float conarea){(4)}void main(){float radius,fence,concrete;cout.setf(ios::fixed);cout.setf(ios::showpoint);cout.precision (2) ;cout "Enter the radius of the pool: ";cin radius;cout "Enter the FencePrice: ";cin fence;cout "Enter the ConcretePrice: ";cin concrete;Circle Pool(radius);Circle PoolRim(radius + WIDTH);Money mon(fence,concrete);float totalmoney=mon.TotalMoney(PoolRim.Circumference(),(PoolRim.Area() - Pool.Area()));cout "The total money is RMB " totalmoney endl;}

考题 ( 13 )补充完整下面的类定义:const double PI=3 .14;class Circle{ // 圆形物体的抽象基类protected:double r; // 半径public:Circle ( double radius=0 ) : r ( radius ) {}【 13 】 ; // 计算圆形物体表面积的纯虚函数声明};class Cylinder:public Circle { // 圆柱体类double h; // 高度public:Cylindr ( double radius=0, doubli height=0 ) :Circle ( radius ) , h ( height ) {}Virtual double Area () { // 计算圆柱体的表面积return 2*PI*r* ( r+h ) ;}};

考题 C++代码的错误在哪 #includeiostreamviod mian(){ const double pi=3.1415926; double radius; double areas; cout"input radius:"endl; cinradius; areas=pi*radius*radius; cout"the areas"radius"is"areas"\n"endl;}哪里有错啊,高手指教???

考题 阅读以下说明和C++代码,将应填入(n)处的字句写在对应栏内。【说明】以下C++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4个类组成:类 Triangle、Rectangle和Square分别表示三角形、矩形和正方形:抽象类Figure提供了一个纯虚函数getAxea(),作为计算上述3种图形面积的通用接口。【C++代码】include<iostream>include<cmath>using namespace std;class Figure{public:virtual double getArea()=0;//纯虚函数};class Rectangle : (1) {protected:double height;double width;public:Rectangle(){}Rectangle(double height, double width){this->height=height;this->width=width;}double getArea(){return (2);}};class Square: (3) {public:Square(double width){(4);}};class Triangle: (5) {private:double la,lb,lc;public:Triangle(double la,double lb,double lc){this->la=la;this->1b=1b;this->lc=lc;}double getArea(){double s=(la+lb+lc)/2.0;return sqrt(s*(s-la)*(s-lb)*(s-lc));}int main(){Figure *figures[3]={new Triangle(2,3,3),new Rectangle(5,8), new Square(5)};for(int i=0;i<3;i++){cout<<"figures["<<i<<"]area="<<(figures[i])->getArea()<<endl;}return 0;}

考题 阅读以下说明和C++代码,填入(n)处。[说明]以下C++代码使用虚函数实现了同一基类shape派生出来的Class rectangle、Class triangle、Class circle实现了计算矩形、圆形面积的计算。仔细阅读以下代码,将(n)处语句补充完整。[代码5-1]include<iostream.h>define PI 3.14159class shape {//基类protected:(1);public:(2);(3);};[代码5-2]class rectangle: public shape {public:rectangle (int x2,int y2,int r2): (4) {};double area ( ) {return x*y; };};class circle: public shape {public:circle (int x3,int y3,int r3):(5){};double area ( ) {return r*r*PI; };};[代码5-3]void main ( ){rectangle r (10,20,0);circle c (0,0,30);shape (6);cout<<"长方形面积="<<s1->area ( ) <<endl;cout<<"圆形面积="<<s2->area ( ) <<endl;}[运行结果]长方形面积=200圆形面积=2827.43

考题 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.interfaeeB.staticC.finalD.abstract

考题 阅读以下说明及C++程序代码,将应填入(n)处的语句写在对应栏内。【说明】本程序的功能是根据矩形左上角和右下角顶点坐标生成一个矩形对象,然后输出该矩形4个顶点的坐标,计算并输出该矩形的面积。【C++代码】include<iostream>using namespace std;class MyPoint( //表示平面坐标系中的点的类double x;double y;public:MyPoint (double x,double y){this->x=x;this->y=y;}double getX()const{(1);}double getY()const{ return y;}void show()const{ cout<<'('<<x<<','<<y<<')';}};class MyRectangle{ //表示矩形的类MyPoint upleft; //矩形的左上角顶点MyPoint down right; //矩形的右下角顶点public:MyRectangle(MyPoint upleft,MyPoint downright);MyPoint getUpLeft()const{return up_left;} //返回左上角坐标MyPoint getDownRight()const{return down_right;} //返回右下角坐标MyPoint getUpRight()const; //返回右上角坐标MyPoint getDownLeft()const; //返回左下角坐标double area()const; //返回矩形的面积};MyRectangle:: MyRectangle((2)):up left(p1),down_right(p2){}MyPoint MyRectangle::getUpRight()const{return MyPoint(down_right.getX(),up_left.getY());}MyPoint MyRectangle::getDownLeft()const{return MyPeint((3));}double (4) ::area()const{return (getUpLeft(),getX()-getDownRight().getX())*(getDownRight().getY()-getUpLeft().getY());}int main( ){MyRectangle r(MyPoint(0,2),MyPoint(2,0));r.getUpLeft(),show();r.getUpRight().show();r.getDown Right().show();(5);cout<<r.area()<<end1;return 0;}

考题 使用VC6打开考生文什夹下的工程test1_3。此工程包含一个test1_3.cpp,其中定义了类circle和column,其中column类由circle类protected派生,但两个类的定义并不完整。请按要求完成下列操作,将程序补充完整。(1)定义类circle的保护数据成员r和area,它们都是double型的数据。请在注释“//**1**”之后添加适当的语句。(2)添加类circle的无参数的构造函数,使circle对象的r默认值为0,请在汁释“//**2**”之后添加适当的语句。(3)添加派生类column构造函数的定义,传入的参数为double型的height和radius,并将具分别赋值给数擗成员h和基类的r,请在注释“//**3**”之后添加适当的语句。(4)完成派生类column的成员函数print的定义,使其以格式“r=_area=_”先输出半径r和底面积area,再以格式“h=_vol=_”输出高h和体积vol的值,请在注释“//**4**”之后添加适当的语句。输山结果如下:r=1 area=3.1416h=2 vo1=6.2832注意:除在指定的位置添加语句外,请不要改动程序中的其他语句。源程序文件test1_3.cpp清单如下:include<iostream.h>const double pi=3.1416;class circle{protected://**1**public://**2**circle(double radius){ r=radius;}void print(){area=r*r*pi;cout<<"r="<<r<<" "<<"area="<<ared<<endl;}};class column: protected circle{protected:double h;public://** 3 **void print(){// ** 4 **}};void main(){column col(1.0,2.0);Col.print();}

考题 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);}}

考题 如下程序声明了一个二维图形类TwoDShape,从其派生出矩形类Rec。 include include 如下程序声明了一个二维图形类TwoDShape,从其派生出矩形类Rec。include<iostream>include<string>using namespaee std,class TwoDShape{// 二维图形类char name[20];public:TwoDShape (char * n="unknown") {strcpy(name, n);}Char * getName(){return name;}【 】=0;};class Rec: public TwoDShape{double width, heightpublic:Rec(double w-=0. 0,double h=0. 0):TwoDShape("rectangle"){ width=w; height=h; }double getWidth() {return width;}double getHeight() {return height;}double area() {return width * height;}};int main() {TwoDShape * shape;Shape=new Rec(2.1,3.0);cout<<"object is"<<shape->getName()<<"\n";cout<<"Area is"<<shape->area()<<"\n";return 0}请将程序补充完整,使程序在运行时输出:abject is triangleArea is 6.3

考题 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.interfaceB.staticC.finalD.abstract

考题 下列程序的执行结果为【 】。include class Point{public:Point(double i, double j) 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)}

考题 阅读以下说明和JAVA 2代码,填入(n)处的。[说明]以下JAVA程序实现了在接口interface iShape2D的定义和应用,仔细阅读代码和相关注释,将程序补充完整。[代码6-1]interface iShape2D //定义接口{(1)(2)}(3)//实现CRectangle类{int width, height;(4) CRectangle (int w,int h) {width=w;height=h;}public void area ( ){ //定义area( )的处理方式System. out.println ("area="+width*height);}}(5)//实现CCircle类{double radius;(6) CCircle (double r) {radius=r;}public void area ( ) { //定义area( )的处理方式System.out.println ("area="+pi*radius*radius);}}[代码6-2]public class app10_4{public static void main(String args[]){CRectangle rect=new CRectangle (5,10);rect.area ( ); //调用CRectangle类里的area ( ) methodCCircle cir=new CCircle (2.0);cir.area ( ); //调用CCircl类里的area ( ) method}}

考题 使用VC6打开考生文件夹下的工程test1_1,此工程包含一个源程序文件test1_1.cpp,但该程序运行有问题,请改正main函数中的错误,使该程序的输出结果如下:Constructor called.Default constructor called.Area is 6Area is 0Area is 6源程序文件test1_1,cpp清单如下:include<iostream.h>class RectAngle{private:double ledge,sedge;public:RectAngle(){cout<<"Default constructor called.";}RectAngle(double l,double s){ledge=l;sedge=s;cout<<"Constructor called.";}void Set(double l,double s){ledge=l;sedge=s;}void Area(){cout<<"Area is"<<ledge*sedge<<endl;}};void main(){/***************** found *****************/RectAngle Rect1(2,3);RectAngle Rect2(1);/**************** found *****************/RectAnglC Rect3;Rectl.Area();/***************** found *****************/RecL2.lodge=0;Rect2.sedge=0;Reck2.Area();Rect3.Area();}

考题 阅读以下说明和C++程序,将应填入(n)处的字句写在对应栏内。【说明】以下程序的功能是计算正方体、球体和圆柱体的表面积和体积并输出。程序由4个类组成:类cube、sphere和cylinder分别表示正方体、球体和圆柱体;抽象类 container为抽象类,提供了两个纯虚拟函数surface_area()和volum(),作为通用接口。【C++程序】include<iostream.h>define pi 3.1416class container{protected:double radius;public:container(double radius) {container::radius=radius;}virtual double surface_area()=0;virtual double velum()=0;};class cube:(1){ //定义正方体类public:cube(double radius):container(radius){};double surface_area () {return 6 * radius * radius;}double volum() {return radius * radius * radius;}};class sphere:(2){ //定义球体类public:sphere(double radius): container(radius){};double surface_area() { return (3);}double volum() {return pi * radius * radius * radius * 4/3;}};class cylinder:(4){ //定义圆柱体类double height;public:cylinder(double radius,double height):container(radius){container::height=height;}double surface_are a () { return 2 * pi * radius * (height+radius); }double volum () {return (5);}};void main(){container * p;cube obj1 (5);sphere obj2(5);cylinder obj3(5,5);p=obj1;cout<<“正方体表面积”(<<p->surface_area()<<end1;cont<<“正方体体积”<<p->volume()<<end1;p=obj2;cout<<“球体表面积”<<p->surface_area()<<end1;cout<<“球体体积”<<p->volume()<<end1;p=obj3;cout<<“球体表面积”<<p->surface_area()<<end1;cout<<“球体体积”<<p->volume()<<end1;}

考题 下列程序中,先声明一个圆类circle和一个桌子类table,另外声明一个圆桌类roundtable,它是由 circle和table两个类派生的,要求声明一个圆桌类对象,并输出圆桌的高度,面积和颜色。请填空完成程序include<iostream.h>include<string.h>class circle{double radius;public:circle(double r){radius=r;}double get_area(){return 3.416*radius*radius;}};class table{double height;public:table(double h)<height=h;}double get_height(){return height;}};class roundtable:public table,public circle{char *color;public:roundtable(double h,double r,char c[]): 【 】 {color=new char[strlen(c) +1];【 】;};char*get_color(){return color;}}:void main(){roundtable rt(0.8,1.0,“白色”);cout<<"圆桌的高:"<<rt. get_height()<<end1;cout<<"圆桌面积:"<<rt.get_area()<<end1;cout<<"圆桌颜色:"<<n.get color()<<end1;}

考题 Interrupts are an important part of embeddedsystems. Consequently, many compiler vendorsoffer an extension to standard C to support interrupts.Typically, the keyword is __interrupt. The followingcode uses __interrupt to define an interrupt serviceroutine (ISR). Point out problems in the code.__interrupt double compute_area (double radius){double area = PI * radius * radius;printf("\nArea = %f", area);return area;}

考题 阅读以下说明和JAVA 2代码,将应填入(n)处的字句写在对应栏内。[说明]以下程序为类类型的变量应用实例,通过异常处理检验了类CCircle的变量的合法性,即参数半径应为非负值。仔细阅读代码和相关注释,将程序补充完整。[JAVA代码]//定义自己的异常类class CCircleException extends Exception{}// 定义类 CCircleclass CCircle{private double radius;public void setRadius ( double r ) (1){if ( r<0 ) {(2)}else(3)}Public void show ( ) {System. out. println ( "area="+3.14*radius*radius );}}public class ciusample{public static void main ( String args[] ){CCircle cir=new CCircle( );(4) {cir. setRadius ( -2.0 )}(5){System. out. println ( e+" throwed" ) ;}cir. show( ) ;}}

考题 使用VC6打开考生文件夹下的工程test18_1,此工程包含一个源程序文件(est18_1.cpp,但该程序运行有问题,请改正程序中的错误,使程序的输出结果如下:Enter x and y:-4 -5xoffset=1yoffset=1angle=45radius=1.41421源程序文件test18_1.cpp 清单如下:include <iostream.h>include <math.h>class point{public:void set(double ix,double iy){x=ix;y=iy;}double xoffset(){return x;}double yoffset(){return y;}double angle ( ){return (180/3.14159)*atan2(y,x);}/**************** found *******************/inline radius ( ){return sqrt(x*x+y*y);}protected:double x;double y;};void main(){point p;double x,y;cout<<"Enter x and y:\n";cin>>x>>y;p.set(x,y);/**************** found *******************/p.x+=5;p.y+=6;/**************** found *******************/cout<<"xoffset="<<p.xoffset()<<end1;cout<<"yoffset="<<p.yoffset()<<end1;cout<<"angle="<<p.angle()<<end1;cout<<"radius="<<p.radius()<<end1;

考题 有以下程序: #includestdio.h double f(double x); main( ) {double a=0; int i; for(i=0;i30;i+=10)a+=f((double)i); printf("%5.of\n",a); } double f(double x) { return x*x+1; } 程序运行后的输出结果是( )。A.503B.401C.500D.1404

考题 请把下面程序补充完整,正确答案是( )。 main( ) { float radius,length,area,volume; printf("Input a radius:"); Scanf("%f",radius); length=2.0*PI*radius; /*引用无参宏求周长*/area=PI*radius*redius; /*引用无参宏求而积*/ volume=PI*radius*radius*radius*3/4; /*引用无参宏求体积*/ printf("length=%.2f,area=%.2f,volume=%.2f\n",length,area,volume); }A.PI=3.1415926B.Const PI=3.14159C.#define PI3.1415926D.Float PI=3.14159

考题 下面哪个表达式正确使用了math()?A、area=newmath().pt*Radius$adiusB、area=math.New().pt*radius$radiusC、area=math.NewInstance().Pt#radius$radiusD、area=mathpt$radius$radius

考题 若程序中定义了以下函数 double myadd(double a,double b) { return(a+b); } 并将其放在调用语句之后,则在调用之前应该对该函数进行说明,以下选项中错误的说明是()A、double myadd(double a,b);B、double myadd(double,double);C、double myadd(double b,double a);D、double myadd(double x,double y);

考题 单选题public class Mycircle {   public double radius;   public double diameter;   public void setRadius(double radius)   this.radius = radius;   this.diameter= radius * 2;   }   public double getRadius() {  return radius;   }   Which statement is true?()A  The Mycircle class is fully encapsulated.B  The diameter of a given MyCircle is guaranteed to be twice its radius.C  Lines 6 and 7 should be in a synchronized block to ensure encapsulation.D  The radius of a MyCircle object can be set without affecting its diameter.

考题 单选题Which statement is TRUE concerning protection of double bottom tanks against excessive pressure? ()A Each vent for the tank must be equal to the area of the tank filling lineB The tanks must be protected by overflowsC The total area of the vents or the overflow shall be at least equal to the area of the fill lineD There must be twice as much vent area as the area of the fill line