A.光照时间越长光电流越大
B.入射光足够强就可以有光电流
C.遏止电压与入射光的频率有关
D.入射光频率大于极限频率才能产生光电子
CD
---If you like the new house, I suggest you buying it.
---But it's really too expensive. I can't______ it.
A.get
B.afford
C.supply
D.support
应采用计算机管理信息系统控制血液()与()。