课外学习小组在探究“弹簧的伸长与所受的拉力的关系”实验时，实验数据如表．
钩码重/N
0
0.5
1
1.5
2
2.5
3
3.5
4
指针位置
22
23
24
25
26
27
28
28.5
28.6
Our school will____some teachers____ America．
—— How many students are there in your class?
—— There are twenty students in our class, five Americans.
重力约4 N的物体可能是 ( )
