MSU Suffering Back Pains from The Acute Lifting Position Question

Help me study for my Engineering class. I’m stuck and don’t understand. you have been hired by an outdoor guide service to evalutae the sesign of this tool they plan to purchase for use by describe what elements of the tool you would review to. determine the quality of design .calculate the magnitude of force and rotational moments acting on elbow and shoulder for 50th percentile man holding 20kg both hands at shoulder height parallel to the ground.