Can someone check this for me? Its easy points!!!!

This is the assignment:
In your journal, give an example of a function. Give the relation as a set of ordered pairs. Use a test such as mapping or the vertical line test to show if your set of ordered pairs is a function. An example of a function could be: distance traveled and time, or the cost of a turkey and its weight. You can list your relation as a set of ordered pairs, or as a table. In either case, you must prove the relation is a function using one of the two tools given to you in the prior lessons.

This is what i put:
The function is the cost of a car vs. the amount of time it takes in hours.
The parts for the repair cost $150 than an ordered pair would be (0, 150). If the labor rate is $50/hr., then another order pair would be (1, 150), (2, 200), (3, 250) etc. Every time, you increase the x-coordinate by 1, you increase the y-coordinate by 50. The relation would be a function because there will not be two different costs that take the same amount of time.