const interestToPayFor = (loanAmount) => {
  const greaterThan2000 = { endOfRange: Money('$2000.00'), interestPerDollar: Money('$0.09'), previousInterestPerDollar: Money('$0.00') };
  const greaterThan5000 = { endOfRange: Money('$5000.00'), interestPerDollar: Money('$0.14'), previousInterestPerDollar: Money('$0.09') };
  const greaterThan10000 = { endOfRange: Money('$10000.00'), interestPerDollar: Money('$0.21'), previousInterestPerDollar: Money('$0.14') };
  let interestAmount = Money('$0.00');
  if (loanAmount.greaterThan(Money('$2000.00'))) {
    interestAmount = interestAmount.plus(calculateInterest(loanAmount, greaterThan2000));
  }
  if (loanAmount.greaterThan(Money('$5000.00'))) {
    interestAmount = interestAmount.plus(calculateInterest(loanAmount, greaterThan5000));
  }
  if (loanAmount.greaterThan(Money('$10000.00'))) {
    interestAmount = interestAmount.plus(calculateInterest(loanAmount, greaterThan10000));
  }
  return interestAmount;
};