If a farmer carries only a single bag of wheat weighing 20 kg on one shoulder, his spinal width is 5 cm, and the centre of gravity of the bag of wheat is 15 cm from his spine, calculate the total spinal compression. The farmer's upper body mass is 50kg. 1. Calculate the moment due to the load on the fulcrum 2. Calculate the tension required on the muscles for counterbalance 3. Total compression = load muscle tension upper body mass