Well, the first dot is the known as the Minimum. Then, the second dot is the 1st Quartile. The dot in the middle of the box with the line through it is the median (2nd Quartile). Then the last dot forming the box is the 3rd Quartile. And the final dot is the 4th Quartile (Also known as the Maximum). In this case, it is asking about the Median...which would be 15.5. Hope this helped!