下列对生物进化理论的理解不正确的是（   ）

如图，已知AB∥DE，∠B=60°，AE⊥BC，垂足为点E．

下列常用实验仪器中，能直接加热的是（   ）

阅读理解
    Hello, my name is Lina. I'm 10 years old. I'm wearing a red dress. Red is my favourite colour and dresses are my favourite clothes. I like to read books. Fish is my favourite food. Amy is my friend. She is 11 years old. She likes green and her favourite clothes are skirts. She likes to play ping­pong. She likes fish, too. But her favourite food is rice and vegetables. We like to drink juice.

某人要把掉落井中并漂浮在水面上的 $1\text{kg}$ 的铁桶打捞上来，井中水面到井口的距离为 $3\text{m}$ ，打捞时，桶中有 $3\text{kg}$ 的水，则把桶从水面打捞到井口人做的有用功为____ $\text{J}$ ，这次打捞桶的机械效率是____．