根据以下内容,回答下面的题目。Insure means to protect _51_ a loss of money.Most people can budget their money so that their income will cover expected expenses _52_ food, clothing, housing, and public services.But, there is no way to know _53_ who will suffer a crisis (危机) such as a serious illness, fire, flood, or a car accident.Such crises usually _54_ great expense.Even if people could predict crises, it would be hard to save enough money to _55_ the expenses.Insurance is a system _56_ a company collects money from many individuals and then pays certain expenses whenever one of those insured individuals is faced with a certain crisis.An insurance policy _57_ how much the insurance costs and how much the company will pay when a policy holder is faced with a certain crisis.There are many different kinds of insurance, _58_ hospital, motor-car and fire.Insurance can be rather expensive but most people buy insurance of some kinD.Insurance is something _59_ people buy and hope they will _60_ need._________
根据材料,回答下面的题目。金是一种具有美丽光泽的贵金属,是人类最早应用的金属之一。金最大的特点是不易氧化,即使在千度高温下也不变色,因此获了“真金不怕火炼”的美誉。在世界上,绝对的纯金是没有的,一般工业用金也不过为99.99%左右。可见“金无足赤”不无科学道理。通常人们所说的纯金(也有称之为赤金、足金的),纯度约在99%。由于纯金的硬度低、塑性好,用它制成的首饰不耐磨,易变形,所以近代很少用纯度很高的金来制作首饰,而是将它配制成K金后再使用。K金是金与其他金属熔合而形成的金基合金。常用于首饰生产的有金铜合金和金银合金。金铜合金微呈紫红;金银合金则略显淡黄;为此,K金首饰在成品之前一般均进行镀金处理。另外,若在金中加入其他金属元素,还可以制成青色、蓝色和红色等各种颜色的K金饰品。K金按其成色高低分为24K,即24成。24K金为纯金,成色最高。l8K金,则说明该合金中含金18成,其他金属占6成。K金首饰的含金量百分比为:8K——33.3%;9K——37.55%;10K——41.7%;l2K——50%;l4K——58.5%;l8K——75%;20K——83.4%;22K——91.67%。目前,在国外K金首饰很流行。英国盛行9K金,美国和西欧则喜欢l4K金,香港最喜欢l8K金首饰。纯金的比重为l9.3,是钢铁的2.5倍。一寸见方的金块约重700克左右,即超过一市斤。下列对纯金的表述,不符合文意的一项是 ( )