夜间驾驶人对事物的观察能力明显比白天差，视距变短。
参考答案：对
（）we would like to assist you，we do not think there is room for a reduction in our price.
A.Even
B.As
C.Much
D.Much as
根据波特五力模型，一个行业的( )时，该行业风险较小。
A．进入壁垒高 B．替代品威胁大C．买卖方议价能力强 D．现有竞争者的竞争能力强
