Domain.CheckingAccount.GetAmount C# (CSharp) Method

        public double GetAmount()
        {
            return amount;
        }

 public void WithdrawAllowsMoreThanCurrentAmountForCheckingAccount()
 {
     IAccount account = new CheckingAccount(36241604394L, 100.0, 70.0, new Customer());
     service.Withdraw(account, 150.0);
     Assert.AreEqual(-50.0, account.GetAmount());
 }