【单选题】It is implied that before the 19th century the development of hotel ______.
A.
went side by side with the development of economy
B.
was quicker when there was no war
C.
played a leading role in British expansion and colonization
D.
stimulated industrial development and international exchange
【单选题】桥梁结构混凝土材料耐久性的基本要求,对于四类环境类别,最大水灰比是( )
【单选题】Taxes _________________ on or before April 15th. Payments __________________ to the government on or before April 15th.
A.
have to pay; must have been sent
B.
have to be paid; must be sent
【单选题】He moved to Germany in _____, when he was in _____.
A.
the late 1990s; his sixties
B.
late 1990s; his sixties
C.
the late 1990s; the sixties
D.
late 1990s; the sixties
【单选题】桥梁结构混凝土材料耐久性的基本要求,对于三类环境类别,最大水灰比是( )
【单选题】桥梁结构混凝土材料耐久性的基本要求,对于二类环境类别,最大水灰比是( )
【判断题】两回转体相交,其表面的交线称为相贯线。相贯线具有共有性和积聚性。
【简答题】机器人的线性运动是指安装在机器人第 轴法兰盘上工具的TCP(Tool Center Point,工具中心点)在空间中做直线运动。
【判断题】线性运动是指机器人工具中心点在空间中做直线运动。