Answer:
The area of the triangle is calculated as thus:

To calculate the perimeter of the triangle, the measurement of the slant height has to be derived;
Let s represent the slant height;
Dividing the triangle into 2 gives a right angled triangle;
The slant height, s is calculated using Pythagoras theorem as thus

The perimeter of the triangle is then calculated as thus;



For the volume of the cone,
when the triangle is spin, the base of the triangle forms the diameter of the cone;

Where 
So, 
So, 
Base on the above illustrations, the program is as follows;
#include<iostream>
#include<cmath>
using namespace std;
void CalcArea(double b, double h)
{
 //Calculate Area
 double Area = 0.5 * b * h;
 //Print Area
 cout<<"Area = "<<Area<<endl;
}
void CalcPerimeter(double b, double h)
{
 //Calculate Perimeter
 double Perimeter = 2 * sqrt(pow(h,2)+pow((0.5 * b),2)) + b;
 //Print Perimeter
 cout<<"Perimeter = "<<Perimeter<<endl;
}
void CalcVolume(double b, double h)
{
 //Calculate Volume
 double Volume = (1.0/3.0) * (22.0/7.0) * pow((0.5 * b),2) * h;
 //Print Volume
 cout<<"Volume = "<<Volume<<endl;
}
int main()
{
 double b, h;
 //Prompt User for input
 cout<<"Base: ";
 cin>>b;
 cout<<"Height: ";
 cin>>h;
 //Call CalcVolume function
 CalcVolume(b,h);
 //Call CalcArea function
 CalcArea(b,h);
 //Call CalcPerimeter function
 CalcPerimeter(b,h);
  
 return 0;
}