【简答题】He have missed the train; he arrived at the train station two hours early.(can't/mustn't)
【简答题】When John arrived at the station, he
found the train already gone. → , he found the train already gone.
【单选题】Why did the man get home late?
C.
The train was cancelled.
【单选题】设有定义 int a[10]={0,0,0,0,0,0,0,0,0,0};则说法正确的是( )。
C.
数组a有10个元素,其中a[0]的值为0,其他元素的值不确定
【单选题】带传动的功率P=10kw,速度v=15m/s,紧边拉力是松边拉力的三倍,即:F 1 =3F 2 。求:紧边拉力F1 。
【简答题】已知静电场的电势函数【图片】,则在(2,3,0)点处的电场强度大小为 。(题中所有量均为SI单位,保留一位小数)
【单选题】数控钻、铣、镗、磨床均属于 _____ 数控车床