原料预热炉点火时，可不开蒸汽吹扫炉膛而直接点火。

So it is today. Schedule disaster, functional misfits, and system bugs all arise because the left hand doesn’t know what the right hand is doing. As work （）, the several teams slowly change the functions, sizes, and speeds of their own programs, and they explicitly or implicitly （） their assumptions about the inputs available and the uses to be made of the outputs. For example, the implementer of a program-overlaying function may run into problems and reduce speed relying on statistics that show how （） this function will arise in application programs. Meanwhile, back at the ranch, his neighbor may be designing a major part of the supervisor so that it critically depends upon the speed of this function. This change in speed itself becomes a major specification change, and it needs to be proclaimed abroad and weighed from a system point of view. How, then, shall teams （） with one another In as many ways as possible. Informally. Good telephone service and a clear definition of intergroup dependencies will encourage the hundreds of calls upon which common interpretation of written documents depends. Meetings. Regular project meetings, with one team after another giving technical riefings, are（）. Hundreds of minor misunderstandings get smoked out this way. Workbook. A formal project workbook must be started at the beginning.

Regular project meetings, with one team after another giving technical riefings, are（）. Hundreds of minor misunderstandings get smoked out this way

A．worthless

B．valueless

C．useless

D．invaluable

一束光线从点A(－1,1)出发经x轴反射,到达圆C: (x－3)²+(y－2)²=1上一点的最短路程是___________

典型的化脓性脑膜炎脑脊液改变是 ()。

A．细胞数增高、蛋白增高、糖增高

B．细胞数增高、蛋白增高、糖正常

C．细胞数增高、蛋白正常、糖增高

D．细胞数正常、蛋白增高、糖下降

E．细胞数增高、蛋白增高、糖下降

可用于体内、体外抗凝血的药物是

A．肝素
B．华法林
C．枸橼酸钠
D．右旋糖酐
E．新抗凝

国家对河道实行（）的原则。

A.按水系统一管理

B.按分级管理

C.按行政区域管理

D.按水系统一管理和分级管理相结合