public void ScenarioCTest()
{
decimal totalCartAmount = 0.0M, totalPromotionDiscount = 0.0M;
AddProduct();
AddPromotionTypes();
AddScenarioCProductToCart();
PromotionEngine promotionEngine = new PromotionEngine(_promotionTypes);
totalCartAmount = _customerCart.GetTotalCartAmount();
totalPromotionDiscount = promotionEngine.GetPromotionDiscount(_customerCart.CustomerItems);
Assert.AreEqual(280, totalCartAmount - totalPromotionDiscount);
}