【单选题】在衡量数据的变异度时,标准差与方差相比,其主要特点是
【简答题】用简便方法计算:(要写计算过程.) ①25×125×8×40 ②52×66+33×52+52 ③37×99 ④45×101.
【单选题】价格处于日内枢轴点下,处于( );在它之上,就处于( )。
【简答题】Content words are changing all the time whereas functional words are stable/fixed, functional words enjoy a ______ frequency in use than content words.
【简答题】content / notional words and functional words