Answer:
.
Step-by-step explanation:
Let C represent total daily charges in dollars and t represent time in hours.
We have been given that a plumber charges $50 for a service call plus $80 per hour.
The amount charged for t hours would be .
The total amount charged for t hours would be .
We are also told that plumber spends no longer than 8 hours a day at any one site, this means that time t have a restriction as:
Therefore, our required cost function would be .