在下列文件中,不便于文件增、删操作的是( )。
A.索引文件
B.连续文件
C.Hash文件
D.串联文件
参考答案:B
解析:因为连续文件是线性存储,每次增、删都要移动元素,代价较大。
(5分)氢气、氧气、氮气、二氧化碳四种气体中,占空气体积分数最大的是(填化学式,以下相同) ;能使带火星木条复燃的是 ;能与氧化铁在一定条件下发生置换反应的是 ;能使紫色石蕊试液变红色的是 ;能使澄清石灰水变浑浊的是 。
W: I need to talk to someone who knows Baltimore well. I’m told you lived there. M: Oh, but I was really young at the time. Q: What does the man mean().
A. He moved to Baltimore when he was young.
B. He can provide little useful information.
C. He will show the woman around Baltimore.
D. He will ask someone else to help the woman.