山东航空学院When asking questions in class, English teachers should ()A:repeat a difficult question aloud until students understand itB:design questions,don't ask for the sake of askingC:make questions logical,
山东科技大学The yielding stresses for two low-carbon steel tensile specimens with length of 50mm and 100mm are S1 and S 2 ,respectively, elongations are5 and10 respectively,then( )A: