Mustang Tobin Lamer competed in Sioux Falls at the Region 2A meet. Lamer finished with a time of 24:03.80. (Photo/Sara Stadem) Matt Larson | Big Sioux Media The Tri-Valley Mustang cross country season came to an end at the Region 2A meet at Yankton Trail Park in Sioux Falls on Wednesday, October 11. The girls…