如图所示为测量（）的原理接线图。
A.接地电阻
B.接触电阻
C.绝缘电阻
D.土壤电阻率
参考答案：D
Over twothirds of the population were believed to have no ___ to the health care in the west rural
area in China. [ ]
A. aid
B.basis
C.belief
D. access
A．U=vBl，流过固定电阻R的感应电流由b到d
B．U=vBl，流过固定电阻R的感应电流由d到b
C．U=vBl，流过固定电阻R的感应电流由b到d
D．U=vBl，流过固定电阻R的感应电流由d到b
vBl
vBl