关于锅炉暖管,下列说法不合适的是()
A.全开主蒸汽阀暖管
B.暖管时间不宜太短
C.暖管应在锅炉汽压稳定后即将投入工作前进行
D.稍开主蒸汽阀进行暖管,并开启疏水阀疏水
参考答案:A
Which of the following statements is true about his friend
A.Writing exhausts his friend.
B.His friend collects a lot of things to write.
C.His friend always has enough material to write on.
D.His friend is doing research to write a paper.
软件开发中常用的结构化生命周期方法,由于其特征而一般称其为( )。
A.原型化模型
B.瀑布模型
C.层次模型
D.螺旋模型