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【简答题】
试设计一台交通灯监测器。要求如下:有 3 个指示灯,分别为红灯 R ,黄灯 Y ,绿灯 G ;每盏单独点亮时为正常工作状态,黄灯和绿灯同时点亮时,也为正常工作状态,其它点亮组合为不正常工作状态。试用 译码器 74LS138 和少量与非门设计。要求写出设计过程,画出电路图。
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【单选题】Even a single letter can ______ the meaning of the word it precedes.
A.
loan
B.
compensate
C.
estimate
D.
transform
【简答题】Directions: There are 2 passages in this section. Each passage is followed by some questionsor unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decid...
【简答题】Section C Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You s...
【单选题】Part II Structure(10 minutes) Directions: This part is to test your ability to construct grammatically correct sentences. It consists of 2 sections. Section A Directions: In this section, there are 10...
A.
although
B.
despite
C.
though
D.
that
【简答题】Reading Comprehension Directions: There are 4 reading passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A , B ,...
【单选题】Tony as well as his brothers and sisters _______ from America.
A.
is
B.
are
C.
were
D.
have been
【单选题】Section C Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You s...
A.
By building more reserves of groundwater.
B.
By drawing water from the depths of the earth.
C.
By developing more advanced drilling devices.
D.
By upgrading its water distribution system.
【单选题】Tony as well as his brothers and sisters______from America.
A.
is
B.
are
C.
have been
D.
were
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