问题 选择题

同温同压下,在3支相同体积的试管中分别充有等体积混合的2种气体,它们是①NO和NO2,②NO2

O2,③NH3和N2。现将3支试管均倒置于水槽中,充分反应后,试管中剩余气体的体积分别为V1、V2、

V3,则下列关系正确的是[ ]

A.V1>V2>V3

B.V1>V3>V2

C.V2>V3>V1

D.V3>V1>V2

答案

答案:B

单项选择题
单项选择题

In 1993, I published a book, The Rage of a Privileged Class, whose central thesis was that even the most gifted African-Americans assumed that they would never crash through America’s glass ceiling—no matter how talented, well educated, or hardworking they were. Few people of any race would claim that true equality has arrived; but so much has changed since Rage came out. Color is becoming less and less a burden; race is less and less an immovable barrier.

My new research explores how that phenomenon is changing the way people of all races view the American landscape. I polled two groups of especially accomplished people of color. One is the African-American alumni of Harvard Business School. The other is the alumni of A Better Chance, a program, founded in 1963, that sends ambitious, talented youngsters to some of the nation’s best secondary schools.

Generations, I concluded from my study, mattered deeply—with their defining characteristics rooted in America’s evolving racial dynamics. Generation 1, in this categorization, is the civil-rights generation—those (born before 1945) who participated in, or simply bore witness to, the defining 20th-century battle for racial equality. It is the generation of whites who, in large measure, saw blacks as alien beings and the generation of blacks who, for the most part, saw whites as irremediably prejudiced. Gen 2s (born between 1945 and 1969) were much less racially constrained—though they remained, in large measure, stuck in a tangle of racial stereotypes. Gen 3s (born between 1970 and 1995) saw race as less of a big deal. And that ability to see a person beyond color has cleared the way for a generation of Believers—blacks who fully accept that America means what it says when it promises to give them a shot.

That new reality made itself clear when I compared black Gen 1 Harvard M. B. A. s with their Gen 3 counterparts. Seventy-five percent of Gen 1s said blacks faced "a lot" of discrimination, compared with 49 percent of Gen 3s. Twenty-five percent of Gen 1s thought their educational attainments put them "on an equal professional footing with white peers or competitors with comparable educational credentials," compared with 62 percent of Gen 3s. Ninety-three percent of Gen 1s saw a glass ceiling at their current workplaces, compared with 46 percent of Gen 3s.

I am not about to make a statistical argument based on these numbers, but the message nonetheless seems clear. In the time since the Gen 1s came on the scene, a revolution has occurred. Those uptight suburbanites who couldn’t imagine socializing with, working for, or marrying a "Negro," who thought blacks existed in an altogether different dimension, who could no more see dining with a black person than dining with a giraffe, have slowly given way to a new generation that embraces—at least consciously—the concept of equality. Americans have, in some substantial way, re-created each other—to an extent that our predecessors might find astounding.

By saying Americans have "re-created each other", the author means()

A. they created their own life by interracial marriage

B. the way they treat each other has become fairer

C. they acknowledge their predecessors’ contribution to racial equality

D. they have re-created their identities in face of racial discrimination