So i am not getting the formula for the last one I'm not sure why it is not coming out. And also for the Fahrenheit my value keeps equaling to 0 I am not sure why.

Code:

//study iomanip to depth for this project
//to define a constant use #define PI 3.14159
#include "stdafx.h"
#include <iostream>
#include <iomanip>
#define PI 3.14159
#define g 9.81
using namespace std;
int main()
{
double Volume,SurfaceArea,Circumference,Area,Sum, SideA;
double Length,Width,Height,SlantHeight,Radius,Value;
int F,K,C; // temperatures
double Number, a, l;
double P,V,R,T
SideA = 15; // This is the base of the triangle
Height = 3;
Area = 1 * SideA * Height / 2;
cout << "\n\t\tThe area of this beautiful triangle = "
<< Area;
//Volume of Sphere
Radius = 6;
Height = 3;
Volume = 4/3 * PI * Radius * Radius;
cout << "\n\t\t The volume of this cone = " << Volume;
//The Sum
Number = 4;
a = 1;
l = 7;
Sum = Number/2 * (a+l);
cout<<"\n\n\n The Sum of this sum = " << Sum;
// I don't know
Radius = 3;
SlantHeight = 4;
Area = PI * Radius * SlantHeight * 1/2;
cout<<"\n\n\n The Area of this = " << Area;
//Celcius
C = 100;
cout << "\n\t\tThe value of 5 / 9 * (F - 32) = "
<< 5/9* (F - 32) << " Farenheit";
//Farenheit
F = 150;
cout <<"\n\t\tThe value of 9 / 5 * C + 32 = "
<< 9/5 * C + 32 <<" Celcius ";
// Last Formula
P = 3;
V = 6;
R = 2;
T = 7;
Number = P*V/T*R;
cout<<"\n\n\t The value of P * V/ T* R = " << Value;
cout << "\n\n\n";
return 0;
}