腹部X线侧位片上，肾结石可表现（）。
A.与脊柱影重叠
B.位于脊柱影前方
C.位于脊柱影后方
D.在椎间隙内
E.与髂骨重叠
参考答案：A
已知电流表的内阻Rg=100Ω，满偏电流Ig=3mA．要把它改装成量程是6V的电压表，应串联的电阻R1= Ω；要把它改装成量程是3A的电流表，应并联的电阻R2=———————— Ω．
---Look! The two boys always come in and go out in pairs.
---That’s really as a saying goes, “_______.”
A．Two heads are better than one
B．Birds of a feather flock together
C．Bad fortunes never come singly.
D．One boy a boy, two boys half boy, three boys no boy
