下列分子中,具有极性键的非极性分子的组合是( )
A.H2、NH3、H2S
B.CS2、BF3、CO2
C.CH3CI、CH2CI2、CH4
D.SO2、NO2、C2H2
答案:B
One of the assumptions of technical analysis is:()
A. all analysts have all current information.
B. security prices move in random fashion.
C. supply and demand are driven by rational and irrational behavior.
根据下面的例句,运用比喻仿写两个句子。(以下三个句子,任选其二)(6分)
山水田园诗是乡村牧童的一支短笛,清新而幽雅,绿林、青山、落日、孤烟,尽收眼底。
边塞诗是 _____________________________________________________
李白诗是 ________________________________________________________
杜甫诗是_____________________________________________________________