如图所示，在测量小车沿斜面下滑的平均速度的实验中，发现小车下滑过程中在相等时间内通过的路程越来越大，则小车的运动是____ 直线运动（选填“匀速”，“加速”或“减速”）；该实验的实验目的是练习用____ 和 ____测平均速度；实验中，测得路程s₁上的平均速度为v₁，路程s₂上的平均速度为v₂，那么，v₁、v₂的大小关系是v₁____ v₂．（选填“＞”、“=”或“＜”）

四个悬挂着的轻质通草小球，静止时的位置关系如图所示，下列说法正确的是（　　）

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根据短文内容, 选择正确答案。

    Hi. I'm Liu Ying. This is my school. It's big and beautiful. There are twenty classes in my school. There are nine hundred(百) students in my school. There are four beautiful gardens in it. There is a building in my school. On the first（第一） floor, there are two offices and a hall. There are six classrooms on the first floor too. On the second floor, there are fourteen classrooms and two toilets. There is a big library and some reading rooms in my school too. I like my school very much.