如图所示,电源电压不变,闭合开关S,滑动变阻器的滑片由b向a移动过程中,下列说法

题型:选择题

问题:

如图所示,电源电压不变,闭合开关S,滑动变阻器的滑片由b向a移动过程中,下列说法中正确的是(  )

A.电流表示数减小

B.电压表、电流表示数的比值增大

C.电路的总功率变大

D.定值电阻R的功率不变

考点:电路故障分析欧姆定律及其应用滑动变阻器电功率的计算
题型:选择题

可用于鉴别霍乱弧菌古典生物型和ElTor生物型的试验是()

A.氧化酶试验

B.多粘菌素敏感试验

C.硝酸盐还原试验

D.鸟氨酸脱羧酶试验

E.耐盐试验

题型:选择题

我行高度重视电子银行业务的发展,经历了2000年~2004年的初创起步阶段和2005年~2008年的快速成长阶段,电子银行业务已经成为我行业务办理的主渠道、市场营销的主战场和客户服务的主要平台,并已经踏上了一个全新的高起点。()

题型:选择题

Research on animal intelligence always makes me wonder just how smart humans are. (91) the fruitfly experiments described in Carl Zimmer’s piece in the Science Times on Tuesday. Fruit flies who were taught to be smarter than the average fruit fly (92) to live shorter lives. This suggests that (93) bulbs burn longer, that there is an (94) in not being too terrifically bright.
Intelligence, it (95) , is a high-priced option. It takes more upkeep, burns more fuel and is slow (96) the starting line because it depends on learning—a gradual (97) —instead of instinct. Plenty of other species are able to learn, and one of the things they’ve apparently learned is when to (98) .
Is there an adaptive value to (99) intelligence That’s the question behind this new research. I like it. Instead of casting a wistful glance (100) at all the species we’ve left in the dust I.Q. wise, it implicitly asks what the real (101) of our own intelligence might be. This is (102) the mind of every animal I’ve ever met.
Research on animal intelligence also makes me wonder what experiments animals would (103) on humans if they had the chance. Every cat with an owner, (104) , is running a small-scale study in operant conditioning, we believe that (105) animals ran the labs, they would test us to (106) the limits of our patience, our faithfulness, our memory for terrain. They would try to decide what intelligence in humans is really (107) , not merely how much of it there is. (108) , they would hope to study a (109) question. Are humans actually aware of the world they live in (110) the results are inconclusive.

A.Suppose

B.Consider

C.Observe

D.Imagine

题型:选择题

AML-M0是指急性髓细胞白血病的()

A.未成熟型

B.成熟型

C.未分化型

D.部分分化型

E.微分化型

题型:选择题

BOD(生化需氧量)是水中有机物在()过程中(即需氧细菌生长的过程中)所必须吸取的氧量

A.生物化学需氧氧化

B.强氧化剂氧化

C.自然氧化

D.自然分解

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