心电图中，正常QTc的最高值为（） ["0.12s","0.20s","0.32s","0.40s","0.44s"]
心电图中，T波的振幅不应低于同导联R波的（） ["1/2","1/4","1/6","1/8","1/10"]
一般正常的Q波时限应（） ["<0.04s","<0.06s","<0.08s","<0.10s","<0.12s"]
正常成人心率在正常范围时，P-R间期为（） ["0.08～0.11s","0.08～0.20s","0.12～0.16s","0.12～0.20s","0.16～0.24s"]
P波振幅在胸导联应该（） ["<0.25mV","<0.2mV","<0.3mV","<0.15mV","<0.1mV"]
医疗仪器设备发展规划和计划要遵循（）、（）、（）的原则。
