如图6-20所示水箱自由出流，1、2、3、4点在同一水平位置上，d3＞d2＞d4，压

下列各组物质中，前者属于混合物，后者属于纯净物的是

A．水银、汽油

B．不锈钢、汽水

C．空气、葡萄糖

D．酒精、生铁

肝气犯胃之胃痛的主症是 （）

A.脘痛连胁

B.嗳气频作

C.大便不畅

D.口干口苦

E.舌红、苔黄

锥型套筒冠义齿戴用后出现缘龈炎，而无其他不适，其可能的原因有（）

A.壁凸度不良

B.内冠边缘过长

C.外冠边深过长

D.咬合早接触

E.龈沟内粘固剂残留

It is said that in England death is pressing, in Canada inevitable and in California optional. Small wonder. Americans’ life expectancy has nearly doubled over the past century. Failing hips can be replaced, clinical depression controlled, cataracts removed in a 30-minute surgical procedure. Such advances offer the aging population a quality of life that was unimaginable when I entered medicine 50 years ago. But not even a great health-care system can cure death—and our failure to confront that reality now threatens this greatness of ours.

Death is normal; we are genetically programmed to disintegrate and perish, even under ideal conditions. We all understand that at some level, yet as medical consumers we treat death as a problem to be solved. Shielded by third-party payers from the cost of our care we demand everything that can possibly be done for us, even if it’s useless. The most obvious example is latestage cancer care. Physicians—frustrated by their inability to cure the disease and fearing loss of hope in the patient—too often offer aggressive treatment far beyond what is scientifically justified.

In 1950, the U. S. spent $12.7 billion on health care. In 2002, the cost will be $1,540 billion. Anyone can see this trend is unsustainable. Yet few seem willing to try to reverse it. Some scholars conclude that a government with finite resources should simply stop paying for medical care that sustains life beyond a certain age—say 83 or so. Former Colorado governor Richard Lamm has been quoted as saying that the old and infirm "have a duty to die and get out of the way" so that younger, healthier people can realize their potential.

I would not go that far. Energetic people now routinely work through their 60s and beyond, and remain dazzlingly productive. At 78 Viacom chairman Sumner Redstone jokingly claims to be 53. Supreme Court Justice Sandra Day O’Connor is in her 70s, and former surgeon general C. Everett Koop chairs an Internet start-up in his 80s. These leaders are living proof that prevention works and that we can manage the health problems that come naturally with age. As a mere 68-year-old, I wish to age as productively as they have.

Yet there are limits to what a society can spend in this pursuit. As a physician, I know the most costly and dramatic measures may be ineffective and painful. I also know that people in Japan and Sweden, countries that spend far less on medical care, have achieved longer, healthier lives than we have. As a nation we may be overfunding the quest for unlikely cures while underfunding research on humbler therapies that could improve people’s lives.

The author’s attitude toward Richard Lamm’s remark is one of ().

A. p disapproval

B. reserved consent

C. slight contempt

D. enthusiastic support

背景资料：

某工程公司在一大厦广场基础工程进行护坡锚杆作业。当天工地主要负责人、安全员、电工等有关人员不在现场，下锚杆钢笼时，班组长因故请假也不在现场，15名民工在无人指导的情况下自行作业，因钢筋笼将配电箱引出的380V电缆线磨破，使钢筋笼带电，事故造成6人伤亡、3任重伤、5任轻伤，直接经济损失约100万元。

这起事故中，操作人员没有违规操作的行为。