A plumber charges a flat fee for a service call plus an hourly rate for labor. The table below shows the total cost for a service call that takes hours.
| Hours (h) | Total Cost C(h) |
|---|---|
| 1 | $95 |
| 3 | $185 |
| 5 | $275 |
What is the plumber's hourly rate?
$45
$50
$95
$185
