自然循环汽包锅炉的自补偿能力是指:()
A.上升管的产汽率随受热增强而加大
B.上升管的循环水流量随受热增强而加大
C.上升管的流动阻力随受热增强而加大
参考答案:B
在Windows的窗口中,单击最小化按钮后____。
A.当前窗口将消失
B.当前窗口将关闭
C.当前窗口缩小为图标
D.打开控制菜单
The most crucial time for project risk assessment is()
A.when aproblem surfaces
B.during the planning phase
C.during the close-out phase
D.after the project schedule has been published