Five 80-W and three 100W are run for 8 hours. If the cost of energy is N5.00 per unit, calculate the cost of running the lamp. [1 unit = 1 kWh]
-
A.
N280.00 -
B.
N28.00 -
C.
N7.20 -
D.
N1.44
Correct Answer: Option B
Explanation
P = (80 x 5 + 100 x 3)8
= 5600W
Cost = (frac{5600}{1000} times 5 = N28)