正方体ABCD﹣A₁B₁C₁D₁的棱长为$\sqrt{2}$，△AB₁D₁面积为____ ，三棱锥A﹣A₁B₁D₁的体积为____ 

根据短文理解，选择正确答案。

    Everyone needs friends. We all like to feel close to someone. It is nice to have a friend to talk, laugh, and do things with. Surely, sometimes we need to be alone. We don't always want people around. But we would feel lonely if we never had a friend.

    No two people are the same. Sometimes friends don't get on well. That doesn't mean that they no longer like each other. Most of the time they will make up(和解) and become friends again.

    Sometimes friends move away. Then we feel very sad. We miss them very much, but we can call them and write to them. It could be that we could even see them again. And we can make new friends. It is surprising to find out how much we like new people when we get to know them.

    There's more good news for people who have friends. They live longer than people who don't. Why? It could be that they are happier. Being happy helps you stay well. Or it could be that they just know that someone cares. If someone cares about you, you should also take good care of yourself.

下列部件中，装在话筒里的有____ （填字母），装在听筒里的有____ （填字母），人对电话话筒说话，话筒把声波转化成强弱变化的____ 

A．水磁铁   B．螺线管   C．碳粒   D．用碳精制成的振动膜   E．碳精盘   F．用铁制成的振动膜．

资料1:苏云金芽孢杆菌是一种细菌，体内有“杀虫蛋白”基因（简称BT基因）。将该基因转入水稻中，可以生产出含有BT蛋白的大米，名为BT大米。BT蛋白能使食用它的昆虫幼虫死亡，但目前尚未发现BT蛋白对哺乳动物有明显的毒害作用。

资料2:—般来说，DNA和蛋白质彻底分解成小分子物质后才能被吸收，即使食用了BT 大米，人体内也不会有BT基因和蛋白。然而，近年来科学家发现，存在未经消化的蛋白质被吸收进入人体的现象。

600×4表示4个600连加，又表示600×4。