Answer:
10
Explanation:
The median is arranged in numerical value.
it goes: 4, 5, 9, 11, 12, 13. The median is basically the number in-between. you would cross out 4 and then 13. next, 5 and 12. Now there's 9 and 11 in the middle and that is what's left. the number in between of 11 and 9 is 10. 10 would be the median of the data set.