球铁管标准规定DN100~DN1000的管伸长率不小于()。
参考答案:0.1%
____ is the first thing to consider when customers buy certain goods. [ ]
A. Reward
B. Quality
C. Value
D. Quantity
如图所示的四个图象的变化趋势,能挣钱描述对应操作的是( )