搜题请搜索小程序“爱下问搜题”
问题 选择题

下列说法中正确的是：[ ]

A、2kg棉花质量与2kg木头质量并不相等

B、将一铁块加热后压扁了，其质量不变

C、一块冰熔化成水后，体积变小，其质量变小

D、宇航员将一块矿石从月球带回地球上，其质量将变小

答案

B

单项选择题

胸出口综合征时阳性的检查是

A．腹痛、发热、黄疸
B．水量便鲜血
C．出血伴腹痛高热
D．出血速度慢、便血为主
E．出血速度快、呕血或便血
查看答案
单项选择题

The history of African—Americans during the past 400 years is traditionally narrated (1) an ongoing struggle against (2) and indifference on the part of the American mainstream, and a struggle (3) as an upward movement is (4) toward ever more justice and opportunity.

Technology in and of (5) is not at fault; it’s much too simple to say that gunpowder or agricultural machinery or fiber optics (6) been the enemy of an (7) group of people. A certain machine is put (8) work in a certain way—the purpose (9) which it was designed. The people who design the machines are not intent on unleashing chaos; they are usually trying to (10) a task more quickly, cleanly, or cheaply, (11) the imperative of innovation and efficiency that has ruled Western civilization (12) the Renaissance.

Mastery of technology is second only (13) money as the true measure of accomplishment in this country, and it is very likely that by (14) this under-representation in the technological realm, and by not questioning and examining the folkways that have (15) it, blacks are allowing. (16) to be kept out of the mainstream once again. This time, however, they will be (17) from the greatest cash engine of the twenty-first century. Inner-city blacks in particular are in danger, and the beautiful suburbs (18) ring the decay of Hartford, shed the past and learn to exist without contemplating or encountering the tragedy of the inner city.

And blacks must change as well. The ways that (19) their ancestors through captivity and coming to freedom have begun to loose their utility. If blacks (20) to survive as full participants in this society, they have to understand what works now.

20（）

A.is

B.were

C.are

D.have
查看答案