在面积为S的平行板电容器内填充介电常数作线性变化的介质,从一极板(y=0)处的ε1连续地变化到另一极板(y=d)处的ε2,试求电容量。
参考答案:
His approach has won him a ________ as a tough manager.[ ]
A. requirement
B. reputation
C. privilege
D. character
流行病学研究中所指的群体:()。
A.病人群体
B.非病人群体
C.一定范围内的群体
D.全人类