一个计算机系统的虚拟存储器的最大容量是由______确定的。A．CPU地址长度 B． 发布时间：2017-12-05 17:25 │ 来源：www.tikuol.com 题型：单项选择题 问题： 一个计算机系统的虚拟存储器的最大容量是由______确定的。A．CPU地址长度B．内存容量C．硬盘容量D．内存和硬盘容量之和
题型：单项选择题 完形填空。 I know a black boy called l . His father is a farm worker. He works in a big 2 in the middle of America. Tom's parents work hard for the family day and night,but they get _ 3 money. So they are _ 4 . Tom_5 a younger brother, Jack and a younger sister, Su-san. The family need Tom's help. On weekends Tom 6 play in the park with other 7 . He has 8 at home to look after his sister, or help his parents 9 their work. Tom is such a twelve-year-old boy. Tom knows China," How happy the 10 children are ! " He often says, "I like this country very much, I will go there one day. "( )1. A. Mary ( )2. A. library ( )3. A. much ( )4. A. rich ( )5. A. has ( )6. A. can ( )7. A. children ( )8. A. to study ( )9. A. in ( )10.A. Chinese B. Tom B. hospital B. many B. poor B. have B. can't B. child B. to play B. on B. Japanese C. Jack C. school C. a littleC. old C. is C. must C. friend C. to work C. with C. AmericanD. Susan D. farm D. little D. young D. there is D. only D. classmate D. to stay D. for D. English 查看答案
题型：单项选择题 生理学家发现，人类掌管记忆和思维等高级认知功能的大脑皮质在正常情况下有6层，如果胎儿缺乏一种名为“Cdk5”的酶，大脑皮质的发育就会变得极为缓慢，无法最终形成正常大脑皮质的6层结构，从而严重影响儿童认知发展。一些医药界人士推测，利用这一发现，将有望研发出药物，普遍提高学生的学习能力。如果以下各项为真，哪项不能质疑上述推测？（）A．人体不能吸收外部补充的“Cdk5”酶B．学生的学习能力主要是通过后天学习获得的C．一些脑部“Cdk5”酶含量高的人学习能力并不突出D．青少年过脑发育关键期后，补充“Cdk5”酶不起作用 查看答案