Dijawab ya dan pakai cara. thx

>>>>Resistansi total<<<<<
Rt = V/I
Rt = 12/3
Rt = 4 Ohm

karna resistor di rangkai seri, maka
R = Rt - 1 Ohm
R = 4 Ohm - 1 Ohm
R = 3 Ohm ---------- (C.)