The study area was a 2200 m by 2200 m forest tract in the Bull Run watershed. To pick sampling locations, I picked 15 pairs of random numbers between 0 and 2200, representing distances along each edge of the study area. I used these numbers as Cartesian coordinates to locate 15 points. At each of the 15 coordinate locations, I recorded the tree basal area of all trees within a 300m2 circular plot centered on the coordinates. I then calculated stand basal area for the location by dividing the sum of the tree basal areas by 300 m2. I repeated this procedure at all 15 locations." Flag question: Question 10 Question 102 pts What was the actual sampling universe? Group of answer choices The Bull Run watershed The forest tract mentioned in the Methods The 15 plots The trees that were measured