【判断题】《论世界》不完整的版本是1664年出版的。()
【单选题】She must be at least eighteen years old. 中 at least 的中文意思是:
【单选题】She must be at least forty years old.
【简答题】She must be at least half a million.
【简答题】一个110V、60W的白炽灯接到50Hz、220V正弦电源上,可以用一个电阻、或一个电感、或一个电容和它串联。试分别求所需的R、L、C的值。如果换接到220V直流电源上,这三种情况的后果分别如何?
【单选题】She must be at least eighteen years old.
【单选题】She must be at least thirty-five years old. In my opinion she ______ .