【单选题】A double suction centrifugal pump impeller has been installed in the reverse direction, and will _____.
A.
have a greater head capacity
B.
operate with increased impeller efficiency
C.
discharge through the suction side of the pump casing
D.
require more power to run the shaft
【单选题】A multistage centrifugal pump can be BEST described as having _____.
A.
two or more impellers housed together in one casing and mounted on a single shaft
B.
a single stepped impeller mounted in a progressively staged casing
C.
a large radial clearance between the impeller and casing to prevent overheating due to
D.
an increase in the discharge velocity of the liquid with a corresponding decrease in pressure through the stages
【单选题】( )是太平天国历史中一个光辉的亮点,使这次农民战争鲜明地不同于历史上的其他农民战争,反映了太平天国领导人向西方寻找真理探索国家出路的努力。
【判断题】内容和形式的辩证统一是图形设计中的普遍规律,在设计过程中,根据图形内容的需要,选择相应的图形表现技法,使图形设计达到形式和内容的统一,创造出反映时代精神、民族风貌的适用、经济、美观的装潢设计作品是包装设计者的基本要求。
【单选题】( )是太平天国历史中一个光辉的亮点,使这次农民战争鲜明地不同于历史上的其他农民战争,反映了太平天国领导人向西方寻找真理探索国家出路的努力。