肝性脑病昏迷期哪个不正确A．可有抽搐B．昏迷C．扑翼样震颤阳性D．脑电图异常

函数y=x²-1 （x∈{-1，0，1，2}）的值域是（　　）

A．[0，3]

B．[-1，3]

C．{0，1，3}

D．{0，-1，3}

目前出现一些不法分子假借“家电下乡”名义，制售假冒伪劣产品，牟取不法利益，这体现了市场调节具有（　　）

A．盲目性

B．滞后性

C．自发性

D．不确定性

下图反映了面对金融危机，保护主义在一些国家蔓延。1929～1933年世界经济危机期间，美国带头大幅度提高关税，从而引发了一场关税大战。其直接影响是

A．资本主义各国间的矛盾日趋尖锐

B．资本主义各国政坛丑闻频出

C．资本主义各国社会危机日益加深

D．资本主义各国政府信誉扫地

一般在火药中加入少量的二苯胺是为了改善火药的( )。

A．力学特性

B．安定性

C．安全性

D．燃烧特性

Virtual reality (or VR (65) is kind of a buzzword these days in computer graphics.VR is artificial reality created by a computer that is so enveloping that it is perceived by the mind as being truly real.VR exists in many (66) .A traditional view of virtual reality uses headsets and data gloves.The headset serves as the eyes and ears to your virtual world,projecting sights and sounds generated by the computer.The data glove becomes your hand,enabling you to interact with this (67) world.As you move your head around,the computer will track your motion and display the right image.VR is the most demanding (68) for computer graphics,requiring hardware and software capable of supporting realtime 3D (69) .

67（）

A.dummy 

B.simulated 

C.fictitious 

D.invented