hi im a new memeber .iv started learning java recently. i was wondering could anyone help with this problem because i just cant seem to work out where i'm going wrong. its my method call thats giving me the proplem...i think. if anybody has any solutions i would be grateful
import javax.swing.*;
public class EurekaWater{
public static void main(String args[]){
String userInput,waterQty;
Double input,quantityWater, fee;
userInput=JOptionPane.showInputDialog("enter number of home Owners");
input=Double.parseDouble(userInput);
for(int count=0; count<input; count++)
{
waterQty=JOptionPane.showInputDialog("Enter quantity of water user in cubic feet");
quantityWater=Double.parseDouble(waterQty);
if(quantityWater<=1000){
fee=FlatRate; }
else if (quantityWater>1000&&quantityWater<=2000){
fee=FlatRatePlus;
}
else if (quantityWater>2000&&quantityWater<=3000){
fee=FlatPlusPlus; }
else {
fee=HigherRate; }
JOptionPane.showMessageDialog(null,fee);
}
}
public static double FlatRate()
{
return 15.0;
}
public static double FlatRatePlus (double units)
{
double cost=(units-1000)*.0175+15;
return cost;
}
public static double FlatPlusPlus (double units)
{
double cost=((units-2000)*.02)+22.50;
return cost;
}
public static double HigherRate (double units)
{ double cost;
return cost=70;
}
} 
Unsolved 
