【判断题】达芬奇是最早论述空气透视及在绘画中运用的人。()
【简答题】A.She thinks his lectures are boring. B.She thinks his tests are too long. C.She doesn't think he prepares well enough. D.She doesn't like his choice of test questions.
【单选题】图示为一铰链四杆机构的运动简图(比例尺为μl)及其图示位置的速度多边形(比例尺为μv,p为极点)和加速度多边形(比例尺为μa,π为极点)。试判断下列哪个分析结果是错误的( )。
A.
相对加速度a CB的加速度影像为b'c',其指向由b' 指向c'
B.
若以构件BC为边,作ΔBCE相似于Δb′c′π且角标字母顺序一致,而求得点E,则E点加速度一定为零
【单选题】发球队员击球时与场上后排队员有位置错误吗()
【单选题】In 1660 the monarchy was restored and Charles I.s son was brought back from()where he had fled for safety.
【简答题】He had fled from the sail.
【单选题】在我国南方沿海一些省份,某些海产品被视为上等佳肴,而内地的许多消费者则觉得味道平常。这在市场细分变量中属于