考研
It took ______ for the world to increase its population from 1 billion to 4 billion.A) 100 yearsB) 145 yearsC) 1975 yearsD) Over two million years
题目
It took ______ for the world to increase its population from 1 billion to 4 billion.
A) 100 years
B) 145 years
C) 1975 years
D) Over two million years
相似问题和答案
第1题：
185 In general, attempts to smooth out period to period resources will _____ the scheduled time and _____ project costs.
A. Increase, decrease.
B. Increase, increase
C. Increase, increase or decrease.
D. Decrease, decrease.
E. Decrease, increase
第2题：
67 In general, attempts to smooth out period to period resources will _____ the scheduled time and _____ project costs.
A. Increase, decrease.
B. Increase, increase
C. Increase, increase or decrease.
D. Decrease, decrease.
E. Decrease, increase
第3题：
In general, attempts to smooth out period to period resources will _____ the scheduled time and _____ project costs.
A.Increase, decrease.
B.Increase, increase
C.Increase, increase or decrease.
D.Decrease, decrease.
E.Decrease, increase.
B
第4题：
4．It __________ eight years to build the Dam(大坝) from 1998 t0 2006．
A．spends
B．costs
C．paid
D．took
第5题：
The approaching 4G mobile communication systems are projected to （ ） still remaining problems of 3G systems and to provide （ ） new services ,from high-quality voice to high-definition video to high data-rate wireless channels.[1分]
A.solve
B.solving
C.reduce
D.increase
第6题：
6 Management reserves are normally defined as a % of the total budget. As a project progresses, the project manager wants the $ value of management reserve to _____, whereas the customer wants the management reserve to _____.
A. Increase, increase.
B. Increase, decrease.
C. Decrease, decrease.
D. Decrease, increase.
E. Remain the same, return to customer
第7题：
88 Management reserves are normally defined as a % of the total budget. As a project progresses, the project manager wants the $ value of management reserve to _____, whereas the customer wants the management reserve to _____.
A. Increase, increase.
B. Increase, decrease.
C. Decrease, decrease.
D. Decrease, increase.
E. Remain the same, return to customer
第8题：
Management reserves are normally defined as a % of the total budget. As a project progresses, the project manager wants the $ value of management reserve to _____, whereas the customer wants the management reserve to _____.
A . Increase, increase.
B . Increase, decrease.
C . Decrease, decrease.
D . Decrease, increase.
E . Remain the same, return to customer.
第9题：
查询订购单号(字符型，长度为4)尾字符是“1”的错误命令是
A．SELECT*FROM订单WHERE SUBSTR(订购单号，4)=“1”
B．SELECT*FROM订单WHERE SUBSTR(订购单号，4，1)=“1”
C．SELECT*FROM订单WHERE“1”$订购单号
D．SELECT*FROM订单WHERE RIGHT(订购单号，1)=“1”
解析：函数SUBSTR(字符表达式，起始位置，长度)表示从指定表达式的起始位置取一个指定长度的子串作为函数值。没有设定长度时，系统默认自定长度为1。 RIGHT(字符表达式，长度)表示从指定表达式的右端取一个指定长度的子串作为函数值，没有设定长度时，系统默认自定长度为1。故选项C为错误命令，选项A和选项B都使用 SUBSTR()作为查询条件，都能够实现从订购单号的第四个字符开始取长度为1的字符串，由于订购单号长度为4，因此取得的结果就是尾字符串。选项D使用RIGHT()函数，从订购单号的末尾取长度为1的字符串，因此也是正确的。选项C中的查询条件“1”$订购单号只能测试字符“1”是否在订购单号中出现，不能测试尾字符是否为“1”。
第10题：
真核生物ITS序列由ITS1和ITS2两部分组成。