【单选题】Why does the author dislike email communication?
A.
Because of fear of new technology.
B.
Because it takes up too much of her daughter's time.
C.
Because one never really gets to know the person at the other end.
D.
Because it is too noisy and disturbs the peace of the house.
【判断题】齿轮传动能保证准确的平均传动比,能在较恶劣的环境下工作。
【判断题】卫星在空间运行的轨迹称为轨道,描述卫星轨道位置和状态的参数称为轨道参数。
【简答题】卫星在空间运行的轨迹称为轨道,而描述卫星轨道位置和状态的参数,称为 。
【判断题】卫星在空间运行的轨迹称为轨道,描述卫星轨道位置和状态的参数称为轨道参数()。
【判断题】描述卫星轨道位置和状态的参数称为轨道参数