①导体的电阻与导体的长度有关

②导体的电阻与导体的横截面积有关

③导体的电阻与导体的材料有关

实验室提供了4根电阻丝，规格、材料如下表

为了验证上述猜想，他们设计了如图所示的实验电路．

       There is no doubt that mothers play an important leading role in the lives of their children. But what about a father's role? I believe that fathers play just as important a role as mothers.
       Fathers give us support. They are the shore（岸）we swim to when our arms and legs feel increasingly tired. They are the strength we rely on （依靠）as we take our first steps into the world. Fathers can be gentle and powerful, but they probably have the simplest love we ever know.
_______, the father is their first hero and possibly the only man they will ever feel comfortable loving.
For daughters, the father is the first man they admire and the first man whose eyes shine with happiness when they look at them. He is the first man to fall in love with them.
        For mothers, the father of our children is the person we can believe in to watch over the babies as closely as we would. We are protectedin the knowledge of their love. A father is the person on the planet with whom we can do whatever we want ... one who will be just as interested and never feel bored in the face of our devotion.
        Without fathers, we wouldn't be mums. I would like to thank them from all our hearts for this honor and for being our partners in the business of raising children.

帮助小动物找车厢。

七十九后面第五个数____， 四十七前面的一个数____，

与五十九相邻的一个数____， 10个十____。

把三句话合为一句话。

早上，我走进教室。

我放下书包。

我认真地做值日。