问题
选择题
使用酒精灯时，错误的操作是
A．用火柴点燃酒精灯
B．用燃着的酒精灯去点燃另一盏酒精灯
C．用酒精灯外焰给物质加热
D．熄灭酒精灯火焰时，用灯帽盖灭
答案
答案：B
考查常见仪器酒精灯的使用。
用燃着的酒精灯去点燃另一盏酒精灯，容易引起火灾，选项B不正确，其余都是正确的，答案选B。
搜题请搜索小程序“爱下问搜题”
使用酒精灯时，错误的操作是
A．用火柴点燃酒精灯
B．用燃着的酒精灯去点燃另一盏酒精灯
C．用酒精灯外焰给物质加热
D．熄灭酒精灯火焰时，用灯帽盖灭
答案：B
考查常见仪器酒精灯的使用。
用燃着的酒精灯去点燃另一盏酒精灯，容易引起火灾，选项B不正确，其余都是正确的，答案选B。
| Modern industrial society grants little status to old people. In fact, such a society has a system of built-in obsolescence. There is no formal system for continuing our education throughout our life in order to keep up with rapidly changing knowledge. When our education and job skills have grown obsolete, we are treated exactly like those who have never gained an education or job skills and are not encouraged or given the opportunity to begin anew. As a society becomes more highly developed, the overall status of older people diminishes. Improved health technology creates a large pool of old people, who compete for jobs with the young. However, economic technology lowers the demand for workers and creates new jobs for which the skills of the aged are obsolete, forcing older people into retirement. At the same time, young people are being educated in the new technology and are keeping pace with rapid changes in knowledge. Finally, urbanization creates age-segregated neighborhoods. Because the old live on fixed incomes, they must often live in inferior housing. All these factors -- retirement, obsolete knowledge and skills, inferior standards of living -- lower the status of the aged in society. A century ago, when one could expect to live only to 50 or so, the life span more or less coincided with the occupation and family cycle. But today the average life span allows for fifteen to twenty years of life after these cycles. It appears that our life span is outpacing our usefulness in society. |
According to this passage, the status of the aged is lowered by their______.
A．forced retirement
B．inferior housing
C．longer life span
D．fixed incomes