28. 如圖(十七)所示電路,\RB=690kΩ、RC=5kΩ、RE=0.75kΩ,若雙極性接面電晶體(BJT)之β=99、VEB=0.7V,則VC為何? (A)-6.1 V (B)-5.1 V (C)4.2 V (D)8.1 V