public void TestIsSufficientQuanity()
        {
            //arrange
            Catering catering = new Catering(fa);

            CateringItem[] items = catering.GetInventory();
            string         code  = items[0].ProductCode; //first item

            // act
            catering.AddMoney("2000");

            //assert
            Assert.IsTrue(catering.IsSufficientQuanity(code, "50"));
        }