What is the best description of the costs of cleaning an office based on this regression analysis?

$*$Source: Retired ICMA CMA Exam Questions.

There is $$25$ of fixed costs and $$75$ of variable costs per hour to clean an office.

There is $$25$ of variable costs per hour and $$75$ of fixed costs to clean an office.

The cost is $$100$ per hour to clean an office.

The cost is $$25$ per hour to clean an office.