### Question:
SimpleTradingFees implements TradingFees { public static SimpleTradingFees percentage(double fee) { return percentage(fee, fee); } protected  SimpleTradingFees(double makerFeeAmount, double makerFeePercentage, double takerFeeAmount, double takerFeePercentage); static SimpleTradingFees amount(double fee); static SimpleTradingFees percentage(double fee); static SimpleTradingFees amount(double maker, double taker); static SimpleTradingFees percentage(double maker, double taker); @Override double takeFee(double amount, Order.Type orderType, Order.Side orderSide); @Override String toString();  }### Answer:
@Test public void testBreakEvenCalculation(){ TradingFees fees = SimpleTradingFees.percentage(1.0); double amount = fees.getBreakEvenAmount(100); assertEquals(101.99, amount, 0.01); double change = fees.getBreakEvenChange(100); assertEquals(1.99, change, 0.01); }