1. The problem is to find the work done to lift a 20 kg sack of potatoes vertically by 6.5 meters. 2. Work done against gravity is calculated using the formula: $$\text{Work} = \text{Force} \times \text{displacement}$$ where Force is the weight of the object. 3. Weight (Force) is given by $$F = mg$$ where $$m = 20$$ kg and $$g = 9.8$$ m/s\(^2\) (acceleration due to gravity). 4. Calculate the force: $$F = 20 \times 9.8 = 196 \text{ N}$$. 5. Calculate the work done lifting the sack 6.5 m: $$W = F \times d = 196 \times 6.5 = 1274 \text{ J}$$. 6. Therefore, the work done to lift the sack is 1274 joules.