Bal b/f 498 Tempos+3 Tempos=498 Tempos Bal c/f
省到水電：Bal b/f TW$23,725+TW$365=TW$24,090 Bal c/f
https://youtu.be/5dcDK580Kgg?si=A3hxrmwVpfHYP0yK
https://youtu.be/IbwDAftSUxs https://youtu.be/8dsz8lr3hUE?si=kj4eUgRzbyvcxdRC https://youtu.be/ZIXqeZOuCIs?si=yM