题目

Swedish businessman Nile Bergqvist is delighted 41____ his new hotel, the world’s first igloo(冰屋) hotel.  42_______ (build) in an small town, it has been attracting lots of visitors but soon the fun will be over. In two weeks’ time Bergqvist’s ice creation 43_______ (be) nothing more than a pool of water. “We don’t see it as a big problem, ”he says. “We just look forward to 44_______(replace)it. ”    Bergqvist built his first igloo in 1991 for an art exhibition. It was 45______ successful that he designed the present one, 46______ measures roughly 200 square mete a、b、c是某弹性绳上的三个质点，沿绳建立x坐标轴。一简谐横波正在沿x轴的正方向传播，振源的周期T=0.4s，t=0.2s时的波形如图所示，则（ ）A．波速为B．质点开始振动时，速度方向沿正方向C．时，质点处于波峰D．0到0.5s内，质点通过的路程为