【单选题】A car accident happened on the highway because of the heavy fog, but no one got seriously injured.
【单选题】So far hundreds of flights ____ because of the heavy fog .
【简答题】单位脉冲函数 的拉氏变换式是( ); 单位阶跃函数 的拉氏变换式是( ); 单位斜坡函数t的拉氏变换式是( ); 单位斜坡函数 的拉氏变换式是( );
【单选题】We were stuck at the airport because of the heavy fog, otherwise we ________ here in time for the conference.
【单选题】All flights ______because of the heavy fog, we had to decide to take the train.
【单选题】Because of the heavy fog, the TV tower was . [ ]
【单选题】—Attention, please. The plane has to be put ______ because of the heavy fog. —Oh, bad luck! We have to wait now.
【简答题】阅读 We regret to inform you that the flight has been delayed because of heavy fog.
【单选题】The flight to New York was ________ because of the heavy fog.