测定值与真值间的差值
A．平均误差B．标准偏差C．绝对误差D．相对误差E．变异系数
参考答案：C
If Newton lived today, he would be surprise by what () in science and technology.
A. had discovered
B. had been discovered
C. has discovered
D. has been discovered
水库中长期水文预报主要是预报（）。
A.来水量
B.洪峰流量
C.库水位
D.峰现时间
