儿童在游戏中所反映的现实生活中事物或现象的范围规定。它构成游戏的内核，这一概念被称为（） ["游戏内容","游戏形式","游戏规则","游戏主题"]
Which two are true about aggregate functions?（） [" You can use aggregate functions in any clause of a SELECT statement."," You can use aggregate functions only in the column list of the SELECT clause and in the WHERE clause of a SELECT statement."," You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns."," You can pass column names, expressions, constants, or functions as parameters to an aggregate function."," You can use aggregate functions on a table, only by grouping the whole table as one single group."," You cannot group the rows of a table by more than one column while using aggregate functions."]
运用市场途径评估时，为了减少评估人员的工作量，一般只要求选择一个参照物。资产的功能越好，资产的价值就越高。
YSP-0.5、YSP-2.0、YSP-5、YSP-10、YSP-15型液化石油气气瓶自制造日期起，第一次至第三次检验周期为4年，第四次检验有效期（）年。 ["2","3","4","5"]
防火类：
空气透视法
