$($a$)$ Determine the joint reaction force $($F$,$ and $B)$ and the muscle force

$($FM$)$ on the tibia of the knee joint when climbing stairs $($shown on the right$).L_M,L_G,L_w,F_G,F_w,$ and $$ are known.

$($b$)$ Let $L_M=0\mathrm{.}06h,L_G=0\mathrm{.}12h,Lw=0\mathrm{.}24h,Fg=0\mathrm{.}07W,Fw=W$ and and $h$ are the body weight and height, respectively$).$ Calculate $F_M,F_J,$ and $B$ for $0=0,30,60$ and $90.$