如图程序,请补充横线处代码。 A: radius*radius*pi B: radius*radius*math.pi C: radius2*math.pi D: radius2*pi

输入一个表示半径的浮点数，计算圆的面积的程序正确的有：（圆周率取3.14，结果保留2位小数） A: radius = float(input())area = 3.14 * radius ** 2print(round(area, 2)) B: radius = float(input())area = 3.14 * radius * radiusprint(round(area, 2)) C: radius = input()print(round(3.14 * radius ** 2, 2)) D: radius = float(input())print(round(3.14 * radius * radius, 2))

输入一个表示半径的浮点数，计算圆的面积的程序正确的有：[br][/br] （圆周率取使用math库中的pi值，结果保留2位小数） A: import math <br> radius = float(input()) area = math.pi * radius ** 2 print(round(area, 2)) B: import math <br> radius = float(input()) area = pi * radius ** 2 print(round(area, 2)) C: from math import pi <br> radius = float(input()) area = math.pi * radius ** 2 print(round(area, 2)) D: from math import pi <br> radius = float(input()) area = pi * radius ** 2 print(round(area, 2))

class Circle{ double radius; void print(){ double pi; System.out.println("周长是："+2*pi*radius); System.out.println("面积是："+pi*radius*radius); }}这段代码有没有错误？ A: 没写构造函数 B: radius没有初始化 C: 没有错误 D: pi没有初始化

The tracks of high-speed train must have a ________ A: longer curve radius B: shorter curve radius C: thinner curve radius D: wider curve radius

如果有以下关于变量赋值的程序代码： float radius = 88.2; double area= 3.14 * radius * radius; System.out.println(area);

The slenderness ratio is the ratio of ( ) A: area of column to least radius of gyration B: length of column to least radius of gyration C: least radius of gyration to area of column D: least radius of gyration to length of column

编写程序,从键盘输入圆的半径,计算并输出圆的面积。以下代码有一个错误,是哪句? import math radius=float(input("请输入圆的半径:")) circumference=2*pi*radius area=pi*radius*radius print("圆的周长为:%.2f" % circumference) print("圆的面积为:%.2f" % area) A: import math B: adius=float(input("请输入圆的半径:")) C: area=pi*radius*radius D: print("圆的面积为:%.2f" % area)

5) Which one of the glowing magnetic field gives the largest magnitude? A: the field 2 cm away from a long, straight wire carrying a current of 3 A B: the field at the center of a flat, compact, circular coil, 2 cm in radius, with 10 turns, carrying a current of 0.3 A C: the field at the center of a solenoid 2 cm in radius and 200 cm long, with 1000 turns, carrying a current of 0.3A D: the field at the center of a long, straight, metal bar, 2 cm in radius, carrying a current of 300 A E: a field of 1 mT

视频中定义的自定义属性,在布局文件引用方式是 A: android:radius B: app:radius C: radius D: android.radius