Issues with double variables in c++ 2011

[Vuhelper]

1.
#include <iostream>
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#include <iomanip>
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using namespace std;
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void printbill(double kwhused, double rate, double charge, double tax, double total)
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{
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// Print Logo
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cout << "pppppp oooooo w w w eeeeeeee rrrrrrr cccccc oooooo" << endl;
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cout << "p p o o w w w e r r c c o o" << endl;
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cout << "p p o o w w w e r r c o o" << endl;
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cout << "pppppp o o w w w eeeeee rrrrrrr c o o" << endl;
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cout << "p o o w w w e r r c o o" << endl;
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cout << "p o o w w w e r r c o o..." << endl;
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cout << "p o o w w w w e r r c c o o..." << endl;
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cout << "p oooooo w w eeeeeeee r r cccccc oooooo ..." << endl << endl;
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// Print column headers
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cout << setw(10) << "KW/H Used" << setw(10) << "Rate" << setw(10) << "Charge" << setw(10) << "Tax" << setw(10) << "Total";
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// Print data
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cout << setw(10) << kwhused << setw(10) << rate << setw(10) << charge << setw(10) << tax << setw(10) << total << endl << endl;
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}
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int main()
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{
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// Declare constant variables(rate, taxrate)
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const double rate = .001;
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const double taxrate = .05;
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// Declare variables
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double charge, kwhused, total, tax;
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// Get kw/hr use
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cout << "Please input number of kilowatts used : " << endl << endl;
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cin >> kwhused;
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cout << endl << endl << endl;
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// Calculate charge
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charge = rate * kwhused;
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// Calculate tax
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tax = charge * taxrate;
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// Calculate total
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total = tax + charge;
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// Call the printbill() function
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printbill(kwhused, rate, charge, tax, total);
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return 0;
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}
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