Aused car salesperson receieves a commission of 1/12 of the sales price of the car for each car he sells. what would the sales commission be on a car that sold for $21,999

In this question, there are numerous important information's that needed to be taken note of. It is already given that 1/12 is the commission received by the salesman on the sales price of a car.
Then
Sales commission of the salesman on the car = (1/12) * 21999
                                                                           = 21999/12
                                                                           = 1833.25 dollars
So the salesman receives a commission of $1833.25 on the sales of the car that was priced at $21999. I hope you have understood the method by which the problem has been solved.

The correct answer will be d. -4