一物体正在匀速下落,则下列有关说法中正确的是( ) A.合力对物体功不为零,机械

题型:多选题

问题:

一物体正在匀速下落,则下列有关说法中正确的是(  )

A.合力对物体功不为零,机械能守恒

B.合力对物体功为零,机械能不守恒

C.重力对物体做正功,重力势能减少

D.重力对物体做正功,重力势能增加

考点:重力势能机械能守恒定律
题型:多选题

某新建技术改造项目,3年末应还项目总货款为800万元。银行利率为i=8%,故每年应存入 ( )万元才能按时还清货款。

A.306.4

B.246.4

C.286.4

D.256.4

题型:多选题

下列各句中,没有语病的一句是[ ]

A.专家指出,针对“山西地震谣言”事件,国家必须加快相关立法和打击力度,来有效遏制网络散播流言这一现象。

B.“屈原投江”“牛郎织女”“登高赏菊”等优美传说对现在的青年越来越陌生,看来我们要加强对我国传统节日文化的宣传。

C.建造“太阳—氢能”住宅是自然和科技结合的尝试,是摆脱依赖矿物能源的希望所在,显示出强大的生命力和对人们的吸引力。

D.2011年博鳌青年论坛,旨在促进全球青年,特别是港澳台青年了解中国在抵御金融危机过程中发挥的建设性作用。

题型:多选题

根据国家计委的规定,工程咨询业应该遵循的原则是()。

A.独立

B.客观

C.公正

D.科学

E.合理

题型:多选题

意识障碍伴瞳孔散大可见于( )

A.巴比妥类中毒
B.毒蕈中毒
C.吗啡类中毒
D.有机磷农药中毒
E.颠茄类中毒

题型:多选题

Americans’ (1) impulses keep generating surprises. Charitable giving plays an even larger role in the (2) . Demand for nonprofit services gets proportionately bigger as a locality’s (3) rises. The philanthropy of the wealthy may not hinge on tax (4) to the degree many believe. The US (5) the world in levels of charitable activity. Some experts see charity as a (6) trait of the US, more than (7) or business. But those forces may be (8) , as many nonprofits, from healthcare to classical music are selling (9) in a marketplace alongside for-profit (10) . Charity is no mere (11) activity. It pays off for society in ways that may (12) the rates of return on many traditional investments. Charity not only helps those on the (13) end but also strengthens the (14) of society at large. Moreover, it appears to make the givers themselves more (15) . The pattern that conservatives are better givers than (16) is less about politics than about charity-linked (17) most common to conservatives, religious commitment, marriage and children, and entrepreneurship. The main point is that more Americans, regardless of ideology, embrace giving as a tool for (18) . The urge to make a difference, and to take (19) in it, outweighs (20) considerations.

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