【简答题】下列属于中国古代园林理水之法的是( )。
【判断题】在变压器绕组匝数、电源电压及频率一定情况下,将变压器的铁心截面积S减小,根据公式Ф m =BS可知,变压器铁心中的主磁通将要减小。
【单选题】下列不属于中国古代园林理水之法的是______。
【单选题】控制图上一般有三条线,在上面的一条虚线称为?( )
【单选题】某剪力墙上标有 JD2 400х300 +3.1000 表示此墙上开有洞口 , 洞口 ( ) 补强钢筋为 3B14
【单选题】某剪力墙上标有 JD2 400х300 +3.1000 表示此墙上开有洞口 ,洞口 ( ) 距本结构层楼面 3100mm.
【判断题】Many small firms prefer the proprietorship while large companies prefer the corporation.
【单选题】Which of the following statements is NOT characteristic of perfect competition?
A.
. All firms produce the same standardized product.
B.
. There are many producers, and each has only a small market share.
C.
. There are many producers; one firm has a 25% market share, and all of the remaining firms have a market share of less than 2% each.
D.
. There are no obstacles to entry into or exit from the industry.
【简答题】农产品质量安全是__________、优质、营养等要素的综合体。