7. 21μC,0.29μC\text{7. }21\mu C,0.29\mu C7. 21μC,0.29μC
3. 5μC,4.0μC\text{3. }5\mu \mathrm{C},4.0\mu \mathrm{C}3. 5μC,4.0μC
6.21μC,1.29μC6.21\mu C,1.29\mu C6.21μC,1.29μC
2.55μC,4.95,μC2.55\mu C,4.95,\mu C2.55μC,4.95,μC