在探究重力和质量的关系实验中，同学们用弹簧测力计来测物体的重力．实验中测得了几组重力和质量对应数值，并将测得的数据在坐标系中描点、连线，绘制成了如图所示的G﹣m图象．

对下图中的逐渐成长的小树正确的理解是(   )

$\frac{1}{3}$ × $\frac{1}{2}$ ____ $\frac{1}{3}$             $\frac{1}{4}$ × $\frac{1}{3}$ ____ $\frac{1}{4}$

$\frac{1}{2}$ ×1____  $\frac{1}{2}$               6× $\frac{1}{2}$ ____6

9× $\frac{7}{2}$ ____9           $\frac{1}{2}$ × $\frac{2}{2}$ ____  $\frac{1}{2}$

$\frac{1}{3}$ × $\frac{1}{4}$ ____ $\frac{1}{3}$             3× $\frac{4}{5}$ ____3

$\frac{3}{4}$ × $\frac{3}{4}$ ____ $\frac{3}{4}$             5× $\frac{1}{3}$ ____5

阅读下列短文, 根据要求完成下列各题。

      Have you heard about “Survival (生存) Holidays”? “Survival Holidays” is for children to go into the lonely place for exciting activities. Now about 1,100 companies are allowed to(被允许) take children into the great outdoors without their parents.

      The reason why people like “Survival Holidays” is that they think being close to nature is good for children. Many children in big cities spend all time watching TV and playing computer games. “Survival Holidays” gives them an important change.

      Is “Survival Holidays” a wonderful idea? Maybe it is. Children need more free time to play. They need to be left on their own, without adults(成年人) disturbing (打扰) them. Parents care too much about their children. They like to see the children being busy with activities that are controlled by adults, but children don’t know what to do when they are in danger. Even something like crossing a small river seems to be a hard challenge. Children are not comfortable with danger. Even small danger like getting their feet wet or falling down seems very terrible to them.

      Many people think the survival activities are good for children. Even years later, they will still remember what they have learned. Some have learned to stay calm in different times. Some have learned how to keep safe. Others have learned how to work in a team. All these skills will help them a lot in their lives.