腔隙性脑梗死的大小一般是()
A.小于2mm
B.2~15mm
C.15~20mm
D.20~25mm
E.大于25mm
参考答案:B
The new model of car is so expensive that it is only________the reach of those with high incomes.[ ]
A. beyond
B. at
C. in
D. within
关于增感屏对影像效果影响的叙述,错误的是()。
A.增加影像的层次
B.降低影像分辨率
C.降低影像颗粒性
D.增加胶片感度
E.增加影像对比度