题干

如图中的图象(折线ABCDE)描述了一汽车在某一直线上的行驶过程中,汽车离出发地的距离s(千米)和行驶时间t(小时)之间的函数关系,根据图中提供的信息,给出下列说法:

①汽车共行驶了120千米;

②汽车在行驶途中停留了0.5小时;

③汽车在整个行驶过程中的平均速度为

80
3
千米/时;

④汽车自出发后3小时至4.5小时之间行驶的速度在逐渐减少.

其中正确的说法共有(   )

A:1个

B:2个

C:3个

D:4个

上一题 下一题 0.0难度 选择题 更新时间:2011-05-19 11:12:25

答案(点此获取答案解析)

A

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