The annual cost is $18.25.
Step 1. years → days
1 yr × (365 days/1 yr) = 365 days
Step 2. days → hours.
365 days × (5 h/1 day) = 1825 h
Step 3. hours → watt-hours
1825 h × 100 W = 182 500 W·h
Step 4. watt-hours → kilowatt-hours
182 500 W·h × (1kW·h/1000 W·h) = 182.5 kW·h
Step 5. kilowatt-hours → dollars
182.5 kW·h × ($0.10/1 kW·h) = $18.25
