Answer:
the cost of operating the light bulb is 72 cents.
Explanation:
Given;
cost of electricity, C = 6 cents / kW.h
power of light bulb, P = 100 W
time of light power consumption, t = 4 hours per day for 30 days
total time = 4 hours x 30 = 120 hours
Power consumed by the light bulb is calculated as;
P = 100 x 120 = 12000 w.h = 12 kW.h
Cost of power consumption = 6 cents/kWh x 12 kWh
= 72 cents
Therefore, the cost of operating the light bulb is 72 cents.