no 8. hambatan total

Rp = [1/R₁ + 1/R₂ + 1/R₃]⁻¹
     = [1 / (3 Ω) + 1 / (6 Ω) + 1 / (2 Ω)]⁻¹ = 1 Ω

Rs = R₄ + Rp + R₅
      = 5 Ω + 1 Ω + 1 Ω = 7 Ω