检查肝囊肿最简便而实用的方法是()
A.MRI
B.CT
C.选择性动脉造影
D.核医学
E.灰阶超声
参考答案:E
解析:B超可确定肝内有无囊肿和囊肿的数目、部位及大小。
观察长方体,判断它的三视图是[ ]
A.三个大小不一样的长方形,但其中有两个可能大小一样
B.三个正方形
C.三个一样大的长方形
D.两个长方形,一个正方形
The CPU does not have to look (66) all of RAM to find the spot it needs. But RAM only (67) the data temporarily. As soon as you switch the computer (68) , all that information disappears from the RAM. When you switch the computer on again, the RAM is (69) , and ready (70) a new program and new data.
(66)处填()。
A.on
B.through
C.for
D.down upon