TD手机功率为()dBm ["A、17","B、21","C、24","D、30"]
能将直线位移转变成角位移的机械装置是() ["丝杠-螺母","齿轮-齿条","蜗轮-蜗杆"]
运杂费迟交金,每迟延1日,按运杂费迟交总额的()核收。 ["l%","3%","1‟","3‟"]
三叶草结构的小区方向角是() ["0/120/240","60/180/300","30/150/270","80/100/320"]
某直线光栅每毫米刻线数为50线,采用四细分技术,则该光栅的分辨力为() ["5mm","50mm","4mm","20mm"]
我国年降雨量年际变化很大。年降水量越少的地方,相对于多年平均情况来说,其年降水量的年际变化()。