如圖所示電路,則電流I=()
A.3A B.4A C.5A D.6A
如圖所示電路,若電流I為2A,則電源電壓E為()
A.10V B.14V C.16V D.18V
如圖所示電路,若所有電阻皆為4Ω,則電流I約為()
A.1A B.1.5A C.2A D.2.5A