1. 8481. What force must be applied to roll a 120-pound barrel up an inclined plane 9 feet long to a height of 3 feet (disregard friction)? L ÷ I = R ÷ E L = Length of ramp, measured along the slope. I = Height of ramp. R = Weight of object to be raised or lowered. E = Force required to raise or lower object. A. 40 pounds. B. 120 pounds. C. 360 pounds