First, we determine the power that the assembly can supply by multiplying the voltage by the current. That is,
Power = voltage x current
Substituting the known values,
P = (15 V)(8 a)
P = 120 watts
To determine the answer to this item, we divide the calculate power of each,
n = 120 watts / 18 watt/light
n = 6.67 lights
The answer to this item is 6.