Which of the following conditions could cause the feed pump for an auxiliary boiler to lose suction?()
A. Increased suction head pressure
B. Decreased feedwater temperature
C. Pump recirculating line being open too much
D. Excessive feedwater temperature
强筋小麦需要的氮肥比弱筋小麦(),氮肥的追肥次数(),追肥更晚(早晚)。
遇有暴风、雨、雪、雾致使作业人员距()看不清调车信号显示时,为天气不良。
A. 200m
B. 400m
C. 600m
D. 800m
通货膨胀对于魏玛共和国时期的无产阶级是一场灾难,对于中产阶级是一种补偿。
A. 正确
B. 错误