Rectangle Area—Complete the Program Your job is to complete the program. When it is complete, the program will ask the user to enter the width and length of a rectangle and then display the rectangle’s area. The program calls the following functions, which have not been written: • getLength – This function should ask the user to enter the rectangle’s length and then return that value as a double . • getWidth – This function should ask the user to enter the rectangle’s width and then return that value as a double . • getArea – This function should accept the rectangle’s length and width as arguments and return the rectangle’s area. The area is calculated by multiplying the length by the width. • displayData – This function should accept the rectangle’s length, width, and area as arguments and display them in an appropriate message on the screen. the not finished cpp are like the following: #include using namespace std; double getLength(); double getWidth(); double getArea(double ,double ); void displayData(double,double,double); int main() { double len,width, area; width=getWidth(); len=getLength(); area=getArea(len,width); displayData(width,len,area); return 0; } double getLength(){ } double getWidth(){ } double getArea(double length,double width){ } void displayData(double width, double length, double area){ }