如图，在平面直角坐标系中，菱形ABCD的顶点C与原点O重合，点B在y轴的正半轴上，点A在反比例函数y=$\frac{k}{x}$（k＞0，x＞0）的图象上，点D的坐标为（4，3）．

    Everybody needs water. Everything needs water. We use water to wash the bowls(碗), clothes and ourselves. We use water to plant trees, flowers and crops(庄稼). Where does all water come from? It comes from clouds.

    Some of rain goes into the ground. Many people get it under the ground. Some rain water goes into the hills. It runs into lakes and rivers. Many people get it there.

①詹天佑接受了任务。

②詹天佑是工程师。