【单选题】设有关系表S(NO,NAME,AGE),其中AGE为年龄字段,则表达式 AGE NOT BETWEEN 18 AND 24 等价于()
【简答题】完形填空 The great ship, Titanic , sailed for New York from Southampton on April 10th, 1912. She was _1 _ 1,316 passengers and a crew of 891. Even _2_ modern standards, the 46,000 ton Titanic was a huge s...
【单选题】8位D/A转换器的输出电压范围为-5~+5V,当输入量为40H时,模拟电压输出值为( )。
【判断题】坍落度是表示塑性混凝土拌合物流动性的指标。
【单选题】8位D/A转换器的输出电压范围为-5~+5V,当输入量为40H时,模拟电压输出值为( )。
D.
2.5V 答案:C 【参考答案】D/A的输入与输出呈比例关系。(5-(-5))/(28-0)=(X-(-5))/(60H-0),计算后,X=(10*40H)/(28-0)-5=(10*)/256-5=-2.5V
【单选题】表达式“AGE BETWEEN 18 AND 24”等价于( ) 。
【简答题】My father was Chief Engineer of a merchant ship, which was sunk in World War Ⅱ. The book Night of the Uboats told the story. Memories In September ,1940,my mother ,sister and I went to Swansea ,where...
【简答题】4 位 D/A 转换器(输出电压范围为 0 ~ 10V ),其分辨率为 ,若此 DAC 的输入为 0001 ,则输出电压大小为 V 。
【单选题】设有关系表S(NO,NAME,AGE),其中AGE为年龄字段,则表达式AGE NOT BETWEEN 18 AND 24 等价于( )
【简答题】表示塑性混凝土流动性的指标为( )。A. 坍落度 B、分层度 C、沉入度 D、维勃稠度