铅蓄电池组在使用中，若出现一个反极电池时，总电压将下降（）
A.2V
B.4V
C.6V
D.8V
参考答案：B
第一次把植物营养体型称为生活型的人是 ( )
A．洪堡德
B．瓦尔明
C．达尔文
D．奥德姆
If the prediction for the earthquake ________ more accurate, we would have been more prepared and many more lives would have been saved.
A．had been
B．was
C．has been
D．were
