Tom ____ the CD player for two weeks.
A.has lent
B.has borrowed
C.has bought
D.has had
答案:C
The students of Class Three _________ on the playground.
A. be B. are C. is
镍镉(Ni - Cd)可充电电池在现代生活中有广泛应用。已知某镍镉电池的电解质溶液为KOH溶液,其充、放电按下式进行有关该电池的说法正确的是[ ]
A.充电时阳极反应:Ni(OH)2-e-+OH-= NiOOH+H2O
B.充电过程是化学能转化为电能的过程
C.放电时负极附近溶液的碱性不变
D.放电时电解质溶液中的OH-向正极移动