Answer: 6 feet describes the center, and 9 feet describes the spread
Explanation:
The center of a data set is mostly considered as the median or the mean
Here mean is 6 (given). And median is also 6. As 6 is exactly at the middle of the data set. (When arranged in ascending order)
Now, one of the way of calculating the spread is calculating the range, here it's given that the range is 9.
Therefore, 6 feet describes the center, and 9 feet describes the spread is correct.