LTE支持的频带范围() ["700M-2600MHZ,","200M-900M,","900M-2700M,","2200M-2600M."]
在测压部位安装的压力表,根据JJG52-1999规定,它的检定周期一般不超过()。 ["A、半年","B、一年","C、两年","D、三年"]
甘味所含的主要成分是() ["挥发油","皂苷","有机酸和鞣质","生物碱","氨基酸和糖类"]
酸味药所含鞣质的主要药理作用是() ["镇静","镇咳、祛痰","利尿消肿","止泻、止血","降低血压"]
当钢中碳含量在()%区间时,由于包晶反应,易产生铸坯角裂漏钢 ["0.08~0.16","0.12~0.22","0.25~0.35","0.08~0.10"]
车辆牌照位置应为:前号牌在车辆前面中部或()侧,后号牌在车辆后面的中部或()侧。