Answer:
3rd option: 118 < 0.20p + 18 < 218
Explanation:
The answer is between 118 and 218:
a=answer
118 < a < 218
Now solve fo a:
Since the charge is $18 plus $0.20/kilowatt hour, the result cost is
18 + 0.20p ==> p=kilowatt hour and 0.20p is the cost per kilowatt hour
Hence, a=18 + 0.20p
Hence, the answer is 118 < 18 + 0.20p < 218 ==> plugin 18 + 0.20p for a
118 < 18 + 0.20p < 218 ==> 118 < 0.20p + 18 < 218