E = P x t = (40 W)(6 h) = 240 Wh
240 Wh = 0,24 kWh
Biaya = 0,24 kWh x Rp 1.000 / kWh = Rp 240,00
Biaya = 0,24 kWh x Rp 1.000 / kWh
= Rp 240,00
Semoga bisa dipahami ya...
selamat belajar !