金属具有广泛的用途，下列金属的用途是利用了金属的哪些物理性质？
（1）古代人们将铜打磨成铜镜______；
（2）将铝压成铝箔做食品包装纸______；
（3）用钨作电灯泡灯丝______．
（1）古代人们将铜打磨成铜镜利用了铜的物理性质有金属光泽；
（2）将铝压成铝箔做食品包装纸是利用了铝的延展性好；
（3）用钨作电灯泡灯丝是利用了钨的熔点高．
故答为：（1）有金属光泽，（2）延展性好，（3）熔点高．
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| One will feel happy when others flatter (奉承) him in his face. It is said that the best way of flattering someone is to give him a "top hat" 1 . A student was going to leave the capital to become 2 official (官员) in a city far away. Before he started, he came to say 3 to his teacher. "It is 4 job to be a good official." his teacher said. "You must be strict 5 yourself and never be careless." "Don't worry about me, sir." The student answered. "I have already 6 anyone hundred top hats, which will 7 those people quite happy." "But we are really gentlemen! 8 could a real gentleman do such a thing?" His teacher was a bit 9 . "Never forget 10 I taught you in class!" " 11 are always right, sir. I also hate such things. But, sir, 12 no one really gentleman like you can be seen in the world now." said the student. It seemed that he had to do so. 13 hearing this, the teacher was pleased. "What you said is true!" "I have 14 one top hat already. Now I have ninety-nine 15 ." the student said to his friend later on when he asked the student what he had talked with the teacher about. | ||||
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