唐雎不辱使命（节选）
      秦王怫然怒,谓唐雎曰：“公亦尝闻天子之怒乎？”唐雎对曰：“臣未尝闻也.”秦王曰：“天子之怒,伏尸百万,流血千里.”唐雎曰：“大王尝闻布衣之怒乎？”秦王曰：“布衣之怒,亦免冠徒跣,以头抢地耳.”唐雎曰：“此庸夫之怒也,非士之怒也.夫专诸之刺王僚也,彗星袭月；聂政之刺韩傀也,白虹贯日；要离之刺庆忌也,仓鹰击于殿上.此三子者,皆布衣之士也,怀怒未发,休祲降于天,与臣而将四矣.若士必怒,伏尸二人,流血五步,天下缟素,今日是也.”挺剑而起。
秦王色挠,长跪而谢之曰：“先生坐！何至于此！寡人谕矣：夫韩、魏灭亡,而安陵以五十里之地存者,徒以有先生也。”

    Ms. Smith lived in a small village. She was born with a silver spoon. When her parents died， they left her a lot of money. After that， she lived on her own. Unfortunately， she became blind after a serious illness. She went to see lots of famous doctors， hut nobody was able to cure her eyes. She felt very sad.

    One day, a man named Tom came to the village where Ms. Smith lived. He heard about her illness and came to her house. He told Ms. Smith that he had much experience. He was sure to cure her eyes. But she must pay him a large amount of money. Ms. Smith agreed. “But you can't get a penny if you fail，" said the lady.

    During the treatment， Tom found Ms. Smith was very rich. There were plenty of good thing in her house. He stole many valuable things from the house. Several weeks later， Tom cured Ms. Smith. The lady could really see with her eyes. When Tom asked for moneys. Ms. Smith refused. She said. '*You haven't cured my eyes. Before I was blind， I could see all the things in my room.    ⑸     ”

Hearing that， Tom stood there and couldn't say a word.

已知a，b，c∈（0，1），则对于（1﹣a）b，（1﹣b）c，（1﹣c）a说法正确的是（　　）

下列方程是一元二次方程的是（　　）