问题
选择题
| — Hello! I haven't seen you for a long time. — Oh, John, ______? |
A. how are you B. how do you do C. how about you D. what are you |
答案
答案：A
搜题请搜索小程序“爱下问搜题”
| — Hello! I haven't seen you for a long time. — Oh, John, ______? |
A. how are you B. how do you do C. how about you D. what are you |
答案：A
度下的伏安特性曲线，要求特性曲线尽可能完整．已知常温下待测热敏电阻的阻值约为4 Ω～5 Ω.热敏电阻和温度计插入带塞的保温杯中，杯内有一定量的冷水，其他备用的仪表和器具有：盛有热水的热水瓶(图中未画出)、电源(3 V、内阻可忽略)、直流电流表(内阻约1 Ω)、直流电压表(内阻约5 kΩ)、滑动变阻器(0～20 Ω)、开关、导线若干．
