质量为m的物体在竖直向上的恒力F作用下以减速上升了H,在这个过程中,下列说法中正

题型:选择题

问题:

质量为m的物体在竖直向上的恒力F作用下以减速上升了H,在这个过程中,下列说法中正确的有         ( )

A.物体的重力势能增加了mgH

B.物体的动能减少了FH

C.物体的机械能增加了FH

D.物体重力势能的增加小于动能的减少

考点:重力势能
题型:选择题

光合作用与化能合成作用的相似点是[ ]

A.都以太阳能作为能源

B.都需要环境中的物质氧化释放能量

C.都能将无机物转变成有机物

D.都是高等生物的代谢类型

题型:选择题

签发联运提单的承运人的责任是()。

A.只对第一程运输负责

B.必须对全程运输负责

C.对运输不负责

D.只对最后一程运输负责

题型:选择题

车身划痕损失险的保险金额共有4个档次,分别为()、()、()和(),每次赔偿实行()的免赔率。

题型:选择题

An examination of corruption provides the basis for rejecting the view that an exact science of society can ever be constructed. As with all other social phenomena that involve deliberate secrecy, it is intrinsically impossible to measure corruption, and this is not merely due to the fact that social science has not yet reached its goal, achievable to be sure, of developing adequate quantifying techniques. If people were ready to answer questions about their embezzlements and bribes, it would mean that these practices had acquired the character of legitimate, taxable activities and had ceased to be corrupt. In other words, corruption must disappear if it is to be measurable.
Which one of the following most accurately states a hidden assumption that the author must make in order to advance the argument above

A.Some people believe that an exact science of society can be constructed.

B.The primary purpose of an exact science is to quantify and measure phenomena.

C.An intrinsic characteristic of social phenomena that involve deliberate secrecy is that they cannot be measured.

D.An exact science of social phenomena that involve deliberate secrecy cannot be constructed.

E.(E) An exact science can be constructed only when the phenomena it studies can be measured.

题型:选择题

辐射段内炉管是(),沿炉衬内壁水平方向往复排列。

A、单路直管

B、双路直管

C、多路直管

D、多路弯管

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