I'm doing some C++ homework, it's for an online class, and my ****ing teacher never answers me back about questions I have. Ultimately I'm having to do it all on my own basically. I feel like I'm close with this one (or maybe not), but a little mixed up. I'm getting an "in function int main" error but don't know where, and "void value not ignored as it ought to be" error on the line: "totalCommission = calcCommission (commission1, commission2, commission3, commission4)". Can anyone help?

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#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;

int main()

{
const double commission = 0.1;

double salesAmount = 0.0;
double totalCommission = 0.0;
double sale1 = 0.0;
double sale2 = 0.0;
double sale3 = 0.0;
double sale4 = 0.0;
double commission1 = 0.0;
double commission2 = 0.0;
double commission3 = 0.0;
double commission4 = 0.0;

void calcCommission(double, double, double, double);
void displayCommission();
void getTotalCommission();


cout << "Enter first saleman's total sales: ";
cin >> sale1;
cout << "Enter second saleman's total sales: ";
cin >> sale2;
cout << "Enter third saleman's total sales: ";
cin >> sale3;
cout << "Enter fourth saleman's total sales: ";
cin >> sale4;

salesAmount = sale1 + sale2 + sale3 + sale4;
cout << "Total sales: " << salesAmount << endl;

totalCommission = calcCommission (commission1, commission2, commission3, commission4);
cout << "Commission: " << totalCommission << endl;



system("pause");
return 0;
}

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