[多选题] 测得三极管的三个电极的电位关系如图所示,由此可知此三极管是()。{111799.png}
A.NPN型管
B.PNP型管
C.工作在放大状态
D.硅材料管
E.锗材料管

[A] Although the impetus behind location-based tracking was public safety, many companies are exploring commercial opportunities as well. Several companies now offer non-emergency tracking for a monthly fee of about $15～$ 25.
[B] Cell phones have become so convenient and affordable that in some cases people are replacing their traditional phones with cell phones. The sophistication of cell phone technology is increasing at a rapid pace. It is important to consider how this technology impacts your privacy when you purchase and use your cell phone.
[C] Groups of friends are also expected to be able to sign-up for location-based tracking services in the future. Companies, seeking to capitalize on popular computer social networks, such as Friendster arid MySpace, would allow friends to track the location of each other. The service would likely work similarly to the social networks on the internet, where one friend would send a message to another asking them to authori