下列物质属于混合物的是（   ）

阅读下面文段，完成小题。
                                                                                                                  陋 室 铭
                                                                                                                         刘禹锡
        山不在高，有仙则名。水不在深，有龙则灵。斯是陋室，惟吾德馨。苔痕上阶绿，草色入帘青。谈笑有鸿儒，往来无白丁。可以调素琴，阅金经。无丝竹之乱耳，无案牍之劳形。南阳诸葛庐，西蜀子云亭。孔子云：“何陋之有？”

根据短文内容，请将单词填写在题号对应的横线上。

    Without doubt, studying international customs can help avoid ____ (difficult) in today's world of cultural crossroads.

    ____ I get to know more international friends, I learn more about cultural “body language”. Not all cultures greet each other the same way, nor ____ (be )they comfortable in the same way with touching or distance between people. Spoken language can ____ (take) full advantage of to communicate with others, they also express their feelings ____ (use) unspoken “language” through physical distance, actions or posture, English people, for example, do not usually stand very close ____ others or touch strangers as soon as they meet.

    However, people from places like Spain, Italy or South American countries approach others ____ (close) and are more likely ____ (touch) them. Most people around the world now greet each other by shaking hands, ____ some cultures use other greetings as well, such as the Japanese, ____ prefer to bow.

过程现象：让小车从斜面顶端由静止滑下，使小车到达三种不同水平面时的初速度_____，发现小车在_____表面上运动状态改变得最慢。

结论方法：若____的物体不受力的作用，它将保持匀速直线运动状态。在实验的基础上，通过理想化推理得出结论，运用的科学方法是____法。

问题讨论：利用上述器材，再增加一个小木块和一把刻度尺，让小车分别从斜面不同高度处由静止滑下，比较木块被推动的____，由此得出物体的动能与____的关系。