Pistons for modern engines are made of _______.
A cast iron
B steel
C aluminum-alloy
D tin-alloy
A.of a serious mien; of a dull or heavy cast or shade
B.tired and ready to fall asleep
C.highly developed and complex
D.very bad or dishonest
A、the actors
B、the plot
C、the music
D、the special effect
A.ast>(i)
B.astchar*,int>(i)
C.astdouble,int>(i)
A.元器件工艺可重复性
B.元器件制造过程控制一致性
C.元器件的批次一致性
D.元器件的可靠性
E.元器件一致性检验合格率