【简答题】测得三极管三个电极对地电位分别为8V、2V、2.7V。试区分三极管的三个电极,并判断它是硅管还是锗管,是NPN型三极管、PNP型三极管?
【单选题】______ is known to us all is that maths is one of the most difficult subjects. [ ]
【多选题】在鉴别性EMB培养基上,在反射光下大肠杆菌菌落不会呈现的颜色是:()
【单选题】为预防佝偻病,服用维生素D制剂预防量一般应至
【简答题】三极管的三个极分别是 、集电极、基极。A. 发射极
【单选题】在鉴别性 EMB 培养基上,在反射光下大肠杆菌菌落呈现的颜色是
【简答题】按要求改写下面句子。 1. Help was often given to him by us. (改为主动语态) We often him . 2. Maths is more difficult than any other subject. (改为同义句) Maths is the difficult all the subjects. 3. I have written to him fo...