The business leaders have decided that their companies will form a(n) ______ to market the product. A: drama B: alliance C: perimeter D: deputy

Cylinder is to can as () A: circle is to square B: perimeter is to area C: cube is to dice D: line is to angle E: arc is to sphere

Border is to country as () A: perimeter is to object B: land is to owner C: road is to street D: area is to volume E: capital is to state

Which of the following are the instrument for visual acuity test? A: Snellen visual chart B: ETDRS visual chart C: Perimeter D: Auto-refractor

定义一个抽象类Shape,它有两个抽象的方法area（）和perimeter（）,分别表示求面积和周长.

Which<br/>of the following are the instrument for visual acuity test? () A: Snellen<br/>visual chart B: ETDRS<br/>visual chart C: Perimeter D: Auto-refractor

仿照【例1-3】，编写求圆周长的C语言程序，求圆周长的函数命名为Perimeter，圆的半径由用户通过键盘输入

定义类Shape表示一般二维图形。Shape具有抽象方法area和perimeter，分别计算形状的面积和周长。试定义一些二维形状类（如矩形、三角形、圆形等），这些类均为Shape类的子类。

定义两个重载函数area,分别用来求圆和矩形的面积;定义两个重载函数perimeter,分别用来求圆和矩形的周长。并在主函数中调用以上重载函数进行测试。提示:函数名相同,形参数量不同可以构成重载。

A pyramidal-shaped box to protect a plant is constructed with 4 lateral faces and an open bottom. What is the lateral area of the box ？（） (1)The base of the pyramid is a polygon with all sides of equal length, and the perimeter of the base is 1 meter. (2)The 1ateral faces are isosceles triangles that have the same size and shape. A: 条件(1)充分，但条件(2)不充分． B: 条件(2)充分，但条件(1)不充分． C: 条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分． D: 条件(1)充分，条件(2)也充分． E: 条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．