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【简答题】
When an ant dies, other ants take it out of the nest, often within an hour after its death. This behavior interests scientists and they wonder how ants know for sure—and so soon—that another ant is dead. One scientist recently came up with a way to explain this ant behavior. Dong-Hwan Choe is a biologist, a scientist who studies animals and plants. He found that ants have a chemical on the outside of their bodies that signals to other ants, “I'm dead—take me away” when it is dead. But there's a question to answer: As we know, if an ant is dead, it stops moving. But when an ant is sleeping or knocked unconscious, it is also not moving. However, other ants don't move the living ant out of the nest. How do they know this ant is not dead? Choe found that ants have another chemical on their bodies, which tells nearby ants something like, “Wait—I'm not dead yet” when it is not dead. Choe suspects that when an ant dies, the chemical that says, “Wait— I'm not dead yet” quickly goes away. When other ants detect the “dead” chemical without the “not dead yet” chemical, they move away the body. To test his theory, Choe and his team put different chemicals on ants. When the scientists used the “I'm dead” chemical, other ants quickly moved the treated ant away. When the scientists used the “Wait—I'm not dead yet” chemical, other ants left the treated ant alone. Choe believes this behavior shows that the “not dead yet” chemical overrides the “dead” chemical when picked up by other ants. And that when an ant dies, the “not dead yet” chemical fades away. Other nearby ants then detect the remaining “dead” chemical and remove the body from the nest. Understanding this behavior can help scientists figure out how to stop ants from invading new places and causing problems.
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【判断题】( ) 饮用牛奶能预防缺铁性贫血的发生。
A.
正确
B.
错误
【单选题】在窗体上画一个命令按钮,名称为Command1。单击命令按钮时,执行如下事件过程,则在弹出的信息框的标题栏中显示的信息是 ______。 Private SubCommand1_Click() a$='software and hardware' b$=Right(a$,8) c$ =Mid(a$,1,8) MsgBox a$ ,, b$ ,c$,1 End Sub
A.
software and hardware
B.
software
C.
hardware
D.
1
【简答题】It is not only your health that will improve if you give up ,(somke) but also the health of your family.
【判断题】树的任意两点之间有且仅有一条路。
A.
正确
B.
错误
【单选题】产生死锁的基本原因是( )和( ) I.作业运行不当;II.系统资源不足;III.系统发生重大故障;IV.资源分配不当;V.资源独占;VI.进程调度过慢;VII.进程推进顺序不当;VIII.系统中进程太多。
A.
I和II
B.
IV和VII
C.
III和V
D.
VI和VIII
【单选题】产生死锁的基本原因是 I . 作业运行不当; II . 系统资源不足; III . 系统发生重大故障; IV . 资源分配不当; V . 资源独占; VI . 进程调度过慢; VII . 进程推进顺序不当; VIII . 系统中进程太多
A.
Ⅰ;Ⅱ
B.
Ⅳ;Ⅶ
C.
Ⅲ;Ⅴ
D.
Ⅵ;Ⅷ
【判断题】树的任意两点之间有且仅有一条路。
A.
正确
B.
错误
【简答题】It is not only your health that will improve if you give up ( smoke) but also the health of your family.
【简答题】在《诗经》中保存民歌做多的是( )
【单选题】在窗体上画一个名称为Command1的命令按钮。单击命令按钮时执行如下事件过程: Private Sub Command1 Click( ) a$=”software and hardware” b$=Right(a$,8) c$=Mid(a$,L,8) MsgBox a$,,bs,CS,1 End sub 则在弹出的信息框标题栏中显示的标题是( )。
A.
software and bardware
B.
hardware
C.
software
D.
1
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