The advantages of connecting electrical devices in parallel with the battery are:

1. Each device gets the full battery voltage.
2. The parallel circuit divides the current through the electrical devices. Each device gets proper current depending on its resistance.
3. Other devices do not get affected if one device is switched OFF/ON. 

Given,

Charge transferred, Q = 96, 000 C
Time, t = 1 hour = 3600 s
Voltage, V = 50 V
Heat generated, H = V$\times$Q
                            = 50 V x 96,000 C
                            = 48,00,000 J 

(a) Highest resistance can be obtained by connecting the four coils in series. Then
R = R₁ + R₂ + R₃ +R₄
R = 4 + 8 + 12 + 24 = 48 Ω. 

(b) Lowest resistance can be obtained by connecting the four coils in parallel.
Then



or