ask Your goal for this conceptual assessment is to compare the work done by your back when you lift a box properly versus when you lift a box "with your back" (i.e., by rotation over without bending your legs}. In doing so, you will a! so compare the force exerted by your back relative to the body and box weights in both lifting positions. You wiil be using the following applet for this conceptual assessment. You may aiter the "Rotation=" slider to view different moments in the lifting motion. You may also click the "Viewr Back Muscle Arc" button to zoom in around the motion of the back muscie, which will be necessary for Part B of the task. Given are the magnitudes of the displayed vectors, and the ta iinto-tai! angie measures curling from the radial vectors to the weight vectors. The related angle measure moving from 1'3 to F3 is always n/ 2. Notice that the magnitude for 1'2 changes throughout the rotation. Rotation = 100% 0 View Back Muscle Arc ||W1|| = 539N \"a\" 2.61m llW2ll = 294N \"T2\" = 0.54111 . ) ||7~B[| 2 .08m Part A] First, your goal is to calculate the ratio of the force exerted by your back {i.e. the magnitude of F3} with the upper body and box weights (represented as the downward vectors W1 and W2} under the proper lifting technique. Assume that the lifter' s spine is perfectly vertical so that their posture mirrors the applet's conguration at a rotation of 100%. You are to then calculate the same ratio under improper lifting techniques and compare the two ratios. Choose 30% as the rotation when calculating the improper technique ratio. Part B) Your nal goal is to estimate and compare the work done by your back when lifting the box under proper and improper techniques. For the proper lifting technique, assume again that the lifter's posture mirrors the applet's conguration at 100% rotation, and assume that the lifting motion is a .85 meter ascent. For the improper technique, notice that F3 is continuousiy changing to match the continuously changing torque created by the lifter's upperdbody weight and box weight. You will need to estimate the work done by breaking apart the lifting motion into three segments so that you can calculate the approximate work over each segment of motion. To break apart the motion in this way, select the "View Back Muscle Arc" buttonr which will zoom in around the force vector representing the lifter's back muscles. Checking the I\"Show Approximate Path" box will hide the continuous arc of the back muscle motion and instead produce three approximating displacement vectors {(11, d3 and d3}, which should be randomized using the "Randomize Paths" button. Displayed are the coordinates of 11 , d; and (I; {record these coordinates for your sol utio n} as well as the direction unit vector for F3 . The rotation still moves F3 along its path. (Hint: This approximation process operates much like a Riemann Sum.) Use your estimation to conclude which lifting technique is truly better for your back