Answer:
$3.15
Step-by-step explanation:
1 dryer: 500 W
6 dryers: 6 × 500 W = 3000 W × (1 kW / 1000 W) = 3 kW
Running 6 dryers for 1 hour: 3 kW × $0.15 kWh = $0.45
Running 6 dryers for 7 hours: $0.45 × 7 = $3.15
