由集成运放 A 1 、 A 2 、 A 3 等元器件组成的反馈放大电路如图所示。 (1)欲使该电路能正常实现电压放大,试用“+”、“-”号分别标出各个运放的同相输入端和反相输入端; (2)判断由A3与R6、R7、R8构成的电路将uo引入到电路输入端的级间交流反馈的极性与组态。 (3)写出电路的闭环电压增益Auf=uo/ui的表达式。要求有详细的推导步骤,分步打分。
【单选题】—It's necessary to limit the speed of electric bikes. —Yes, most riders of electric bikes in China 40-50 kilometers per hour often ignore red lights, the risk of traffic accidents. [ ]
【判断题】Harry’s Bikes currentratio is 1.3. The industry average for the current ratio is 1.2. This indicatesthat Harry’s Bikes can cover its short term liabilities with its short termassets.