What is the median of the data set 4kg, 4kg, 6kg, 8kg, 13kg

Fist you would put them in order and then cross one off from each side so like 4kg and 13kg and the last two that you have you would add the 4kg and the 6kg and divide by 2 to get the aswer of 5kg.

4kg+6kg=10kg

10kg/2kg=5kg

The median is the value  separating the higher half from the lower half of the data set if the number of terms are odd then the median the middle of the sorted set if the number of terms is even then the median is the arithmetic mean of the two middle elements  of the sorted set

6kg

what type of charge does it have? negative