小儿最常用的药物剂量计算方法是（）
A.按坐高计算
B.按体重计算
C.按年龄计算
D.成人剂量减半
E.按体表面积计算
参考答案：B
Great as Newton was, many of his ideas_____today and are being modified by the work of scientists of our time.
A．are to challenge
B．have challenged
C．are challenging
D．have been challenged
CA0140车床主轴回转精度主要靠什么保证？如何调整？
