小明骑自行车上学途中，要经过一段上坡路。他猜想物体冲上粗糙程度相同的斜坡的最大距离可能与斜坡与水平面的夹角的大小有关。为了验证猜想，小明将两块与水平面平滑连接的长木槽分别以与水平面一定夹角α、θ固定，如图所示，将右边的木槽作为实验研究的斜坡。让一金属小球从左边的木槽上同一高度处静止滚下，分别冲上与水平面的夹角不同的粗糙程度相同的右边的斜坡，测得的数据记录如下表：

① 根据表中数据可知：同一物体以相同的初始速度冲上与水平面的夹角不同的粗糙程度相同的斜坡，____ 。
② 小明觉得自己的实验中还有不足之处，他又用粗糙程度与木槽不同的塑料槽、钢槽，重复做猜想实验，目的是____ 。

过抛物线$y^2=4x$的焦点$F$的直线交抛物线于$A,B$两点,点$O$是原点,若$\left|AF\right|=3$;则$△AOB$的面积为  （　　）

    Students at a primary school in Fuzhou, Fujian Province were required to clean the school toilets to help them develop good habits. But some parents are1against the idea. They can't see the advantages of students doing such chores(杂事). They think that the school2students with a proper education, not the chance to be school 3.In fact, parents, schools and society all play4important role in5 the character of students. It is good 6 schools to give students such tasks, because only 7students will do them at home. Their parents want8to do homework9can help them get good marks.

    In recent years, some parents will make mountains out of molehills(小题大做) when students10to do some chores in schools. If their kids get hurt in schools, some11 about the teachers. Some may even challenge the schools' teaching methods and management.   As a result, many primary schools, especially those in big cities, do not let students12 outdoor activities during breaks because they fear that the students might get hurt. This is bad for the 13development

    What the primary school in Fuzhou is doing is worth praising. Doing chores can put a sense of responsibility into students' minds. It teaches them the spirit of rules and teamwork14.Besides, students' experiences can become15than only studying in schools.