1. The problem statement, all variables and given/known data A 1270-kg car coasts on a horizontal road with a speed of 18.1 m/s. After crossing an unpaved, sandy stretch of road 28.4 m long, its speed decreases to 11.3 m/s. Was the net work done on the car positive, negative, or zero? b. Calculate the magnitude of the average net force on the car in the sandy section. 2. Relevant equations W = F(delta r)(cos theta) 3. The attempt at a solution I started looking at it. I understand work but for some reason I am stuck here.