As a pickup truck (total mass of 2500 kg, including fuel and driver) approaches a rise in an otherwise flat road, the driver presses the clutch and begins to coast. Initially, the truck was moving at 26 ms. For many reasons, including friction losses, the truck has slowed to 10 ms upon reaching the top of the rise (the change in elevation was 25 m). What was the total change in the mechanical energy of the truck in kJ? (Hint: it will be negative.)