解方程:(1)(x﹣1)2=4 (2)x2﹣4x+1=0 (3)3x2+5(2x

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问题:

解方程:(1)(x﹣1)2=4          

(2)x2﹣4x+1=0

(3)3x2+5(2x+1)=0

(4)3(x﹣5)2=2(5﹣x)

考点:一元二次方程的解法
题型:计算题

短文填空

To make sure that there was enough   78  for his sister’s wedding meal(婚宴), Ma missed four school days. He   79  the time carrying water from a lake, 30 miles away from his home. “How I wish I could live   80  a river,” said Ma.

This is the dream of many in northern China.   81  it has the world’s third largest quantity(数量)of water, China is    82  of the 13 thirstiest(最干旱的) countries.

The areas that are in most need of water are western and northern China, where there is   83  rain. These areas have just six percent of the country’s total water, but that water has to feed one third of Chinese people. Much of the water comes from underground. But using much underground water has made the ground sink(下沉)in some places.

Things are getting   84  worse because people are wasting water. Half of the water that farmers use for crops goes to waste. Factories use more water   85  they need and they put dirty water into rivers and lakes. The less water there is, the more worried people will be. How can we use water in a smart way? It’s a question for you to think about on World Water Day, Mar 22.

题型:计算题

早在西汉时期,我国就用铁与硫酸铜溶液反应制取铜,称为“湿法炼铜”。求:

(1)请写出“湿法炼铜”的化学方程式_______________。

(2)若用该方法制得铜32g,反应的铁的质量_______g,若同时消耗了500g硫酸铜溶液,则该硫酸铜溶液中硫酸铜的质量分数为_______%。

题型:计算题

防止油脂酸败的措施是什么?

题型:计算题

关税配额是指______

A.对进口商品既有配额(超过配额,不许进口),又要征收进口关税
B.对关税配额内的进口商品征收低关税、减税或免税,对超过关税配额的进口商品征收高关税
C.一国免税进出口的数量限额,超过限额的进出口要缴纳常规关税
D.发达国家对发展中国家的进口优惠限额,超过限额的不能享受优惠待遇

题型:计算题

根据企业破产法律制度的规定,在人民法院受理破产案件并通知债权人和发布公告后,债权人应当在法定期限内向人民法院申报债权,逾期未申报债权的,视为自动放弃债权,在破产程序中不再予以清偿。债权人向人民法院申报债权的法定期限为( )。

A.收到通知后的10日内,未收到通知的自公告之日起1个月内

B.收到通知后的15日内,未收到通知的自公告之日起1个月内

C.收到通知后的1个月内,未收到通知的自公告之日起3个月内

D.收到通知后的1个月内,未收到通知的自公告之日起6个月内

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