铸件中产生集中缩孔的原因是合金的（）值大于固态收缩值。A.液态收缩 B.凝固收缩 C

环境污染的特点是（）

A.环境污染影响的范围广

B.对人群健康影响时间长

C.环境污染物的种类繁多对人群健康的影响是多种多样的

D.对人群健康的影响常为复杂的多因果关系

E.以上都是

Virtualization is an approach to IT that pools and shares__（71）__so that utilization is optimized and supplies automatically meet demand．Traditional IT environments are often silos, where both technology and human __（72）__。 are aligned around an application or business function．With a virtualized __（73）__，people, processes, and technology are focused on meeting service levels, __（74）__ is allocated dynamically, resources are optimized, and the entire infrastructure is simplified and flexible．We offer a broad spectrum of virtualization__（75）__that allows customers to choose the most appropriate path and optimization focus for their IT infrastructure resources．

（74）处填（）。

A．content

B．position

C．power

D．capacity

在80286中，BU可以预先提取_____个字节指令队列，由_______在与EU并行执行时将其解码。

道路里程桩的设置是在中线丈量的基础上进行的，一般丈量和设置的顺序是（）。

A、先丈量后设置

B、先设置后丈量

C、丈量和设置同时进行

D、无所谓

柴油机的点燃方式为（）。

A.点燃

B.压燃

C.自燃

D.火花塞