Answer: There are 60060 ways to do so.
Explanation:
Since we have given that
Number of linden trees = 6
Number of white birch trees = 4
Number of bald cypress trees = 3
Total number of trees = 6 +4 +3 =13
So, Number of ways that the landscaper plant that trees are evenly spaced is given by

Hence, there are 60060 ways to do so.