高钾血症是指血清钾超过()
A.2.5mmol/L
B.3.0mmol/L
C.3.5mmol/L
D.5.5mmol/L
E.6.5mmol/L
参考答案:D
William found it increasingly difficult to read,for his eyesight was beginning to ________.[ ]
A.disappear
B.fall
C.fail
D.damage
将分割后具有芽眼的马铃薯块茎埋在地里繁育薯苗,该生殖方法属于()。
A.有性生殖
B.分裂生殖
C.出芽生殖
D.营养生殖