An electric elevator with a motor at the top has a multistrand cable weighing 3 lb/ft. When the car is at the first floor, 140 ft of cable are paid out, and effectively 0 ft are out when the car is at the top floor. How much work does the motor do just lifting the cable when it takes the car from the first floor to the top? The amount of work required is |ft-lb. (Simplify your answer.)