A worker performs a simple lifting task of picking up a box container. Below is given information on the container and characteristics of the worker. The most extreme spinal posture position observed during the course of the lift was trunk flexion of $60.$ Assume the worker$$s arms are perpendicular with the floor and his legs are straight. Weight of container $($WC$)=20$kg $($mass$)$ Body Weight $($BW$)=800$ N; Upper$-$body weight $=50\%$ of BW Distance from L$5/$S$1$ joint to center of mass of trunk $($CMTr$)=0\mathrm{.}24$m Segment length of trunk $($SLTr$)=0\mathrm{.}36$m Angle of trunk from horizontal $($T$)=30$