MINNEAPOLIS, Minnesota — Freestyle marathon skiers took to the hills of Theodore Wirth Park for the final day of the 2018 Masters World Cup, in a warm way to wind down the championship week. With sun and temperatures upwards of 40 degrees Fahrenheit by noon, skiers had quite the slog over the 10 k, mostly manmade loop. As Minneapolis native Kitty Earl-Torniainen, 50, described her experience in the 30-kilometer freestyle, “[The course] was nice and...