Answer:
C. It is the total cost of the membership fee and the tire pressure check for 12 months.
Step-by-step explanation:
The constant represents the sum of costs that are <em>not</em> "per car." Those are only "membership fee" ($50) and "tire pressure check" ($15/mo × 12 mo = $180).
First you'd convert the seconds into minutes by dividing.
18,000 / 60 (60 secs in a min) = 300 minutes
Then, similarly, you would convert the minutes into hours.
300 / 60 (60 mins in an hr) = 5 hours
The answer is 5 hours.