(Ted and Bob are having breakfast.)

Ted：Hi, Bob! Eating fried chicken？ ____

Bob：Eggs and milk? I don't want to have them every day.____

Ted：But don't have too much unhealthy food.____

Bob：OK. I won't. By the way, I find some students throw away eggs and milk.

Ted：That's too bad ____

Bob：Yes. But what do you think we can do?

Ted： ____

Bob：Let's have a try，then we may have different kinds of food every day.

已知：如图，AB和DE是直立在地面上的两根立柱，AB=5m，某一时刻，AB在阳光下的投影BC=4m．

（1）请你在图中画出此时DE在阳光下的投影；

（2）在测量AB的投影长时，同时测出DE在阳光下的投影长为6m，请你计算DE的长．

    施先生“双向思考法”：

    正向思考：没有功劳也有苦劳，只要耕耘，一定有收获。

    反向思考：没有效益，方向错误的苦劳，只是徒劳无功。做事要有方法，才能事半功倍。

请你也用这种思考法对“美梦”进行分析阐述。