Given that 1 unit of electricity costs 80 frs. Determine the cost of using 5 living lamps, each rated 120 W, switched on for 4 hours each day throughout the month of June.

Here's the solution to your problem: Problem: Given that 1 unit of electricity costs 80 frs. Determine the cost of using 5 living lamps, each rated 120 W, switched on for 4 hours each day throughout the month of June. Step 1: Determine the total power of all lamps. There are 5 lamps, and each lamp has a power rating of 120 W. Total Power (P) = Number of lamps × Power per lamp P = 5 × 120 \, W P = 600 \, W Step 2: Convert the total power from watts to kilowatts. P = 600 \, W1000 \, W/kW P = 0.6 \, kW Step 3: Calculate the total operating hours for the month of June. The lamps are switched on for 4 hours each day. The month of June has 30 days. Total Time (t) = Hours per day × Number of days t = 4 \, h/day × 30 \, days t = 120 \, h Step 4: Calculate the total energy consumed in kilowatt-hours (kWh). Energy (E) = Power (P) × Time (t) E = 0.6 \, kW × 120 \, h E = 72 \, kWh Step 5: Calculate the total cost. The cost of 1 kWh (1 unit) is 80 frs. Total Cost = Total Energy × Cost per unit Total Cost = 72 \, kWh × 80 \, frs/kWh Total Cost = 5760 \, frs 3 done, 2 left today. You're making progress.