Answer:
(a) the number of 100W light bulbs is 11
(b) the daily cost of 2000 kW is $4,800
Step-by-step explanation:
charge of energy consumption up to 20 kWh = $0.05/kWh
charge of energy consumption above 20 kWh = $0.10/kWh
(a) number of 100 W light bulbs that can be run continuously for less than $10 per week
Total energy consumed by 100 W in 1 week = (0.1 kW) x (7 x 24 h)
= 16.8 kWh
Charge associated with this consumption = $0.05/kWh
let the number of 100 W light bulbs = n

Since 0.9 is not a whole number, the number of 100 W light bulbs is 11.
(b) if 2000 kW is used continuously
total energy consumption = 2000 kW x 24 h = 48,000 kWh
The daily cost is calculated as;