Need help with Java homework

Question

I need help with my homework. My task is to create a program that creates an object Till, accepts payment, issues exact changes, tells me which coins I need to use, and then tells me how much it costs to the end. Below is the code I wrote. The class USmoneyis up and running. The teacher offered a cheat sheet. However, it is the main class ( CoinCalc), receiving payment and subtracting the payment from the amount paid to give me a change that I am having problems with. Any help would be most appreciated.

public class USmoney {
  int dollars = 0;
  int cents = 0;

  public USmoney(int newcents) {
    dollars = newcents /100;
    cents = newcents %100;
  }
  public USmoney(int dollars, int cents) {
    this.dollars = dollars;
    this.cents = cents;
  }

  public int getDollars() {
    return dollars;
  }

  public int getCents(){
    return cents;
  }
}

public class CoinCalc {
  public static void main(String[] args) {
    USmoney Till1 = new USmoney(100,0);
    USmoney billTotal = new USmoney(49);
    USmoney amountPaid = new USmoney(100);

    double penny = 1;
    double nickel = 5;
    double dime = 10;
    double quarter = 25;

    double[] Coin = new double []{penny,nickel,dime,quarter};

  }

  private void changeFor(USmoney billTotal, USmoney amountPaid) {
  }
}

Answer 1

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public USMoney subtract(final USMoney value);

public double[] getCoins(final USMoney value);

Answer 2

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Answer 3

changeFor() CoinCalc. -, CoinCalc main() :

CoinCalc cc = new CoinCalc();

cc.changeFor(billTotal, amountPaid);

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USMoney changeFor(float bill, USMoney paid), USMoney. :

USMoney change = till.changeFor(bill, amountPaid);

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Answer 4

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billTotal amountPaid. .

Then make some variables hold on to how many changes you are returning. For each quarter, penny, nickel, penny, if changeRemaining is the value of a coin, add a coin and subtract the value. Do this for each coin until this coin value passes the test, and then move on to the next coin.