下列关于纬线特点的表述，正确的是[ ] A．所有纬线等长 B．所有纬线都是半圆

一个完整的市场体系应当具备的基本功能包括()。

A.提高资源配置效率 

B.为市场主体提供经济联系的场所和载体 

C.实现商品市场和要素市场之间的信息沟通和传递 

D.较为真实地反映商品和要素的市场价值 

E.对国民经济运行进行宏观调控

外交团

骨髓穿刺术

True, some of the attacks against whites by blacks are for money and valuables. But, others ale revenge assaults by blacks for a real or imagined racial insult. It is equally true that the vast majority of violent crimes against whites are committed by whites, while the vast majority of violent crimes against blacks are committed by other blacks. Yet even after discounting crimes that are hastily and erroneously (错误地，不正确地) tagged as racially motivated, many blacks do attack whites because they all white. A 1998 Justice Department study confirmed that nearly 20% of the more than 4,000 hate crimes well committed against whites, and their attackers were blacks. The Southern Poverty Law Center also notes that there is a huge escalation in black-on- white violence from nearly none at the beginning of the 1990s.
A collection of white supermacists and rightist extremist groups have eagerly made black-on- white violence a wedge issue in their movement to paint blacks as the prime racial hate mongers in America. The New Century Foundation, an ultra-conservative think-tank, has launched a full- blown national campaign to alert whites to the danger of black hate crimes. These groups and individuals magnify hate crimes by blacks in order to back their social agenda. They oppose affirmative action programs and per hate crime laws. They downplay, or justify, the proliferation of white-supremacist-tinged paramilitary groups, police violence, and racial profiling. And they lobby hard for more prisons, police, and tougher laws.
Black-on-white violence also reinforces white fears of blacks as the ultimate menace to society. When blacks say or do nothing about these attacks, it is taken by some as a tacit signal that blacks put less value on white lives than black lives. This is a terrible price for black silence on hate crimes committed by blacks.

Besides the racially motivated crimes, there are indeed crimes committed by blacks against whites for ______.

A. job
B. family
C. money and valuables


D. promotion

氧化氮分离器的温度应小于（）℃。

A.50

B.60

C.70

D.80