电动机调速系统的( )是指在动态扰动下，实际值从开始波动到恢复至偏差带±δ%、且不再超出偏差带的时间。
A. 调节时间
B. 响应时间
C. 动态调节时间
D. 跳变时间
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共用题干题 CT示右额顶区有一直径0.5cm大小高密度阴影，最可能的是
A. 出血
B. 梗死
C. 肿瘤
D. 增生的颅骨
E. 骨折的碎片
In the last sentence of the passage, the phrase "these tools" refers to ______.
A. weather forecasts
B. economic advantages
C. mathematics and physics
D. meteorological problems
用于电动机保护的断路器欠电压脱扣器必须保证在85%～110%UN(UN为电源额定电压)下能长期工作，当电压降到( )时释放。
A. 30%～60%UN
B. 40%～80%UN
C. 35%～70%UN
D. 45%～80%UN
The author implies that increased accuracy in weather forecasting will lead to______.
A. a higher number of professional forecasters
B. less-specialized forms of synoptic meteorology
C. more funds given to meteorological research
D. greater protection of human life
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