报表记录分组操作时．首先要选定分组字段，在这些字段上值______的记录数据归为同一组。
参考答案：相等
解析： 报表记录按照分组字段值是否相同来分组。
______ in the centre of the city, the school is _______ quiet. [ ]
A. Locating; somewhere near
B. Locating; nowhere near
C. Located; nowhere near
D. Located; somewhere near
若某明渠均匀流渠壁粗糙系数n=0.025，水力半径R=0.5m，则其沿程阻力系数λ为：（）
A.0.0261
B.0.0617
C.0.0452
D.0.0551
