DropDownList控件Item集合的Count属性值是（）。

Dependent demand for an item exists when the demand for that item is unrelated to the demand for other items. If any item is 要获取用户对DropDownList对象的选中项的内容，应该使用其（）属性。 News item 5 The opportunity cost of an item is（） You are allowed one carry -on item and one personal item on most flights, and they are both subject to size restrictions. You are allowed one carry-on item and one personal item on most flights, and they are both subject to size restrictions. A debit item in the balance of payments is: The main international payment item is（） 控件组合了TextBox控件和ListBox控件的功能（） ()控件组合了TextBox控件和ListBox控件的功能。 6. This news item is about . item1.setEnabled（true); A push operation adds an item to the top of a（　　）. Button?是一个复合控件，子控件有下列哪个控件()。 下列哪个控件是容器控件（） 阅读以下代码,运行结果为( )。[2,3,4,5].reduce(function(total,item){return total+item;}); The phrase “distracted driving” in Item 5 means ____. In News Item 1, the phrase “in a row” means ______. The correct meaning of a lexical item in a given context is _____.